diff --git a/qt6-after/qt6-migrated-legatus/Lts/Services/CentralEffectSimulation/Plugins/Explosions/expand_polygon.cpp b/qt6-after/qt6-migrated-legatus/Lts/Services/CentralEffectSimulation/Plugins/Explosions/expand_polygon.cpp
index ea0920103..c1aed9abb 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Services/CentralEffectSimulation/Plugins/Explosions/expand_polygon.cpp
+++ b/qt6-after/qt6-migrated-legatus/Lts/Services/CentralEffectSimulation/Plugins/Explosions/expand_polygon.cpp
@@ -11,8 +11,8 @@
 
 #include <CentralEffectSimulation/logger.h>
 
-#include <arcgis/PolygonBuilder.h>
-#include <arcgis/GeometryEngine.h>
+#include <PolygonBuilder.h>
+#include <GeometryEngine.h>
 
 namespace CesExplosions
 {
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/layer_factory.h b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/layer_factory.h
index 1254621ac..7f63fabeb 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/layer_factory.h
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/layer_factory.h
@@ -12,7 +12,7 @@
 #include "situation_map_types.h"
 #include <Common/situation_map_logging.h>
 
-#include <arcgis/arcgisversion.h>  // This file is created by RME, not ESRI
+#include <arcgisversion.h>  // This file is created by RME, not ESRI
 
 // Qt
 
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/map_initializer.cpp b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/map_initializer.cpp
index 00ca18673..2da6bc731 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/map_initializer.cpp
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/map_initializer.cpp
@@ -18,7 +18,7 @@
 #include <Rubberbands/event_mouse_navigator.h>
 #include <LtsCoordTrans/lts_coord_trans.h>
 
-#include <arcgis/arcgisversion.h>  // This file is created by RME, not ESRI
+#include <arcgisversion.h>  // This file is created by RME, not ESRI
 
 #include <QtCore/QCoreApplication>
 #include <QtCore/QJsonDocument>
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.cpp b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.cpp
index 5a5a210d9..8cafdc71f 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.cpp
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.cpp
@@ -12,13 +12,13 @@
 
 
 // Esri
-#include <arcgis/CoreTypes.h> // for LicenseStatus
-#include <arcgis/MapTypes.h>
-#include <arcgis/Viewpoint.h>
-#include <arcgis/Camera.h>
+#include <CoreTypes.h> // for LicenseStatus
+#include <MapTypes.h>
+#include <Viewpoint.h>
+#include <Camera.h>
 
 
-#include <arcgis/arcgisversion.h>  // This file is created by RME, not ESRI
+#include <arcgisversion.h>  // This file is created by RME, not ESRI
 
 #if ACRGIS_VERSION >= 0x640600 // 100.6.0 / Update 6
 #define HAS_SURFACEPLACEMENT_RELATIVETOSCENE
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.h b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.h
index 174412c6a..2a5ef816b 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.h
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Map/situation_map_utils.h
@@ -13,8 +13,8 @@
 
 
 // arcgis
-#include <arcgis/SceneViewTypes.h> // SurfacePlacement
-#include <arcgis/Error.h>
+#include <SceneViewTypes.h> // SurfacePlacement
+#include <Error.h>
 
 
 // Qt
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Symbology/symbol_dictionary.h b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Symbology/symbol_dictionary.h
index d6282af9b..c15b6a6f1 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Symbology/symbol_dictionary.h
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/Symbology/symbol_dictionary.h
@@ -26,7 +26,7 @@ class QValidator;
 
 
 #ifdef BUILD_ARCGIS
-# include <arcgis/arcgisversion.h>  // This file is created by RME, not ESRI
+# include <arcgisversion.h>  // This file is created by RME, not ESRI (300: flat include layout, no arcgis/ subdir)
 
 #if ACRGIS_VERSION >= 0x640600 // 100.6.0 / Update 6
 //# define USE_ARCADE_SYMBOLOGY
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.cpp b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.cpp
index 6cb6e4770..0dab0a53a 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.cpp
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.cpp
@@ -18,8 +18,9 @@
 
 
 // arcgis
-#include <TaskWatcher.h>
 #include <DictionarySymbolStyle.h>
+#include <MapTypes.h>   // Esri::ArcGISRuntime::LoadStatus (300: enum class; Loadable.h only forward-declares it)
+#include <Error.h>      // Esri::ArcGISRuntime::Error (complete type; 300 dropped Error::code())
 
 
 // Qt
@@ -31,6 +32,9 @@
 #include <utility>
 #include <QMimeData>
 #include <QtCore/QTimer>
+#include <QtCore/QFuture>
+#include <QtCore/QFutureWatcher>
+#include <QtGui/QImage>
 
 
 namespace AdvancedSymbology
@@ -159,7 +163,7 @@ QString BaseSymbolItem::symbolSet()
 {
   if (m_symbolSet.isEmpty())
   {
-    SidcDefinitions::SymbolSet symbolSet = SidcDefinitions::castToSymbolSet(m_symbolProperties.originalKey().left(2).toUInt() // Qt6: leftRef removed);
+    SidcDefinitions::SymbolSet symbolSet = SidcDefinitions::castToSymbolSet(m_symbolProperties.originalKey().left(2).toUInt()); // Qt6: leftRef(2) removed
     m_symbolSet = QString(QStringLiteral("%1 - ")).arg(static_cast<int>(symbolSet)) + AdvancedSymbology::SidcDefinitions::toString(symbolSet);
   }
   return m_symbolSet;
@@ -167,7 +171,7 @@ QString BaseSymbolItem::symbolSet()
 
 int BaseSymbolItem::symbolSetAsInt()
 {
-  return static_cast<int>(SidcDefinitions::castToSymbolSet(m_symbolProperties.originalKey().left(2).toUInt() // Qt6: leftRef removed));
+  return static_cast<int>(SidcDefinitions::castToSymbolSet(m_symbolProperties.originalKey().left(2).toUInt())); // Qt6: leftRef(2) removed
 }
 
 
@@ -222,23 +226,32 @@ QImage BaseSymbolItem::getSearchSwatch()
 //    qCritical() << " SEARCH: id=" << m_id << " create swatch now";
 //    qCritical() << " SEARCH: id=" << m_esriSearch.m_esriSymbol->toJson();
 
-    connect(m_esriSearch.m_esriSymbol, &Esri::ArcGISRuntime::Symbol::createSwatchCompleted,
-            this, &BaseSymbolItem::onEsriSearchSymbolSwatchCompleted, Qt::UniqueConnection);
-
-    const Esri::ArcGISRuntime::TaskWatcher &tw = m_esriSearch.m_esriSymbol->createSwatch(SWATCH_SIZE, SWATCH_SIZE, 1);
-    if (tw.isValid())
-      m_esriSearch.m_esriTaskUuid = tw.taskId();
+    // ArcGIS 300: no TaskWatcher / createSwatchCompleted — createSwatchAsync() returns a
+    // QFuture<QImage>; a per-request QFutureWatcher delivers the QImage on the main thread.
+    const QFuture<QImage> fut = m_esriSearch.m_esriSymbol->createSwatchAsync(SWATCH_SIZE, SWATCH_SIZE, 1);
+    if (fut.isValid())
+    {
+      m_esriSearch.m_esriTaskUuid = QUuid::createUuid();   // in-flight guard (was the 100.x task id)
+      QFutureWatcher<QImage> *watcher = new QFutureWatcher<QImage>(this);
+      watcher->setFuture(fut);
+      // 300/Qt6: the 'result' signal is name-collision-ambiguous with the result() getter (QOverload
+      // can't disambiguate); connect to the unambiguous finished() signal and read the value via the
+      // result() getter (the future is finished when finished() fires).
+      connect(watcher, &QFutureWatcher<QImage>::finished, watcher,
+              [this, watcher] {
+        onEsriSearchSymbolSwatchCompleted(watcher->result());
+        watcher->deleteLater();
+      });
+    }
     else
-      qCritical() << " SEARCH: id=" << m_id << " taskId invalid";
+      qCritical() << " SEARCH: id=" << m_id << " createSwatchAsync future invalid";
   }
   return m_esriSearch.m_esriSwatch;
 }
 
-void BaseSymbolItem::onEsriSearchSymbolSwatchCompleted(const QUuid &taskId, const QImage &image)
+void BaseSymbolItem::onEsriSearchSymbolSwatchCompleted(const QImage &image)
 {
-  if (m_esriSearch.m_esriTaskUuid != taskId)
-    return;
-
+  // ArcGIS 300: the dedicated QFutureWatcher makes the (removed) taskId stale-check unnecessary.
   m_esriSearch.m_esriSwatch = image;
 
   emit dataChanged(m_id);
@@ -251,9 +264,6 @@ QImage BaseSymbolItem::getFetchSwatch() const
 
   if (m_esriFetch.m_esriSwatch.isNull() && m_esriFetch.m_esriFetchTaskIdUuid.isNull())
   {
-    connect(m_esriDictionary, &Esri::ArcGISRuntime::DictionarySymbolStyle::fetchSymbolCompleted,
-            this, &BaseSymbolItem::onEsriFetchCompleted, Qt::UniqueConnection);
-
     // from key8 to sidc (20 digits)
     const QString &key8 = m_symbolProperties.key().left(8);
 
@@ -272,39 +282,57 @@ QImage BaseSymbolItem::getFetchSwatch() const
     const QVariantMap keys({{QStringLiteral("sidc"), m_esriFetch.m_sidc},   // SidcCodec::decodeRawSidc ; set sidc of symbol in case of MIL2525
       {QStringLiteral("sic"),  m_esriFetch.m_sidc}}); // SidcCodec::decodeRawSidc , set sidc of symbol in case of APP6
 
-    const Esri::ArcGISRuntime::TaskWatcher &tw = m_esriDictionary->fetchSymbol(keys);
-    if (tw.isValid())
-      m_esriFetch.m_esriFetchTaskIdUuid = tw.taskId();
+    // ArcGIS 300: no TaskWatcher / fetchSymbolCompleted — fetchSymbolAsync() returns a
+    // QFuture<Symbol*>; a per-request QFutureWatcher delivers the Symbol* on the main thread.
+    const QFuture<Esri::ArcGISRuntime::Symbol *> fut = m_esriDictionary->fetchSymbolAsync(keys);
+    if (fut.isValid())
+    {
+      m_esriFetch.m_esriFetchTaskIdUuid = QUuid::createUuid();   // in-flight guard (was the 100.x task id)
+
+      BaseSymbolItem *const self = const_cast<BaseSymbolItem *>(this);   // this method is const
+      QFutureWatcher<Esri::ArcGISRuntime::Symbol *> *watcher = new QFutureWatcher<Esri::ArcGISRuntime::Symbol *>(self);
+      watcher->setFuture(fut);
+      // 300/Qt6: connect to finished() and read the Symbol* via the result() getter (see above).
+      connect(watcher, &QFutureWatcher<Esri::ArcGISRuntime::Symbol *>::finished, watcher,
+              [self, watcher] {
+        self->onEsriFetchCompleted(watcher->result());
+        watcher->deleteLater();
+      });
+    }
     else
-      qCritical() << " FETCH: id=" << m_id << " m_esriFetchTaskIdUuid invalid";
+      qCritical() << " FETCH: id=" << m_id << " fetchSymbolAsync future invalid";
   }
   return m_esriFetch.m_esriSwatch;
 }
 
-void BaseSymbolItem::onEsriFetchCompleted(const QUuid &taskId, Esri::ArcGISRuntime::Symbol *symbol)
+void BaseSymbolItem::onEsriFetchCompleted(Esri::ArcGISRuntime::Symbol *symbol)
 {
-  if (m_esriFetch.m_esriFetchTaskIdUuid != taskId)
-    return;
+  // ArcGIS 300: the dedicated QFutureWatcher makes the (removed) taskId stale-check unnecessary.
 
   // save intermediate result:
   m_esriFetch.m_esriSymbol = symbol;
 
-  // start creating swatch of fetched symbol:
-  connect(m_esriFetch.m_esriSymbol, &Esri::ArcGISRuntime::Symbol::createSwatchCompleted,
-          this, &BaseSymbolItem::onEsriFetchSymbolSwatchCompleted, Qt::UniqueConnection);
-
-  const Esri::ArcGISRuntime::TaskWatcher &tw = m_esriFetch.m_esriSymbol->createSwatch(SWATCH_SIZE, SWATCH_SIZE, 1);
-  if (tw.isValid())
-    m_esriFetch.m_esriSwatchTaskUuid = tw.taskId();
+  // start creating swatch of fetched symbol (createSwatchAsync -> QFuture<QImage>):
+  const QFuture<QImage> fut = m_esriFetch.m_esriSymbol->createSwatchAsync(SWATCH_SIZE, SWATCH_SIZE, 1);
+  if (fut.isValid())
+  {
+    m_esriFetch.m_esriSwatchTaskUuid = QUuid::createUuid();   // in-flight guard (was the 100.x task id)
+    QFutureWatcher<QImage> *watcher = new QFutureWatcher<QImage>(this);
+    watcher->setFuture(fut);
+    // 300/Qt6: connect to finished() and read the QImage via the result() getter (see above).
+    connect(watcher, &QFutureWatcher<QImage>::finished, watcher,
+            [this, watcher] {
+      onEsriFetchSymbolSwatchCompleted(watcher->result());
+      watcher->deleteLater();
+    });
+  }
   else
-    qCritical() << " FETCH: id=" << m_id << " taskId invalid";
+    qCritical() << " FETCH: id=" << m_id << " createSwatchAsync future invalid";
 }
 
-void BaseSymbolItem::onEsriFetchSymbolSwatchCompleted(const QUuid &taskId, const QImage &image)
+void BaseSymbolItem::onEsriFetchSymbolSwatchCompleted(const QImage &image)
 {
-  if (m_esriFetch.m_esriSwatchTaskUuid != taskId)
-    return;
-
+  // ArcGIS 300: the dedicated QFutureWatcher makes the (removed) taskId stale-check unnecessary.
   m_esriFetch.m_esriSwatch = image;
 
 //  qCritical() << " FETCH: id=" << m_id << " image " << image.size();
@@ -426,7 +454,7 @@ void BaseSymbolModel::onLoadStatusChanged(Esri::ArcGISRuntime::LoadStatus loadSt
 void BaseSymbolModel::onErrorDictionary(const Esri::ArcGISRuntime::Error &error)
 {
   FATAL_LOG(m_logger) << LOGFUNCTION << " ---EsriError--- occured: "
-                      << " code="                << error.code()
+                      << " code="                << error.arcGISServerErrorCode().value_or(-1)   // 300: Error::code() removed
                       << ", domain="             << static_cast<int>(error.domain())
                       << ", extendedErrorType="  << static_cast<int>(error.extendedErrorType())
                       << ", message='"           << error.message() << "'"
@@ -456,13 +484,15 @@ void BaseSymbolModel::initModel(SymbolDictionary *symbolDictionary,
 
     // spend time to create (expensive) Esri::ArcGISRuntime::Symbol?
 #ifdef LTS_DEBUG
-  Esri::ArcGISRuntime::Symbol *esriSymbol = nullptr;
+  Esri::ArcGISRuntime::Symbol *esriSymbol = nullptr;   // 300: filled asynchronously (see below)
   const bool showAll = QGuiApplication::keyboardModifiers().testFlag(Qt::KeyboardModifier::ControlModifier);
-  if (showAll)
-    esriSymbol = searchResult.symbol(this);    // symbol() has to be called from mainThread, is expensive / time consuming
+  // 300: symbol() (const, sync, mainThread) is gone; fetchSymbolAsync() is non-const + async.
+  // When showAll, the Symbol is fetched after the item exists and attached via
+  // setEsriSearchSymbol() when the future completes.
 #else
     // release mode: save time, won´t be visible
     Esri::ArcGISRuntime::Symbol *esriSymbol = nullptr;
+  const bool showAll = false;
 #endif //   LTS_DEBUG
 
 
@@ -470,6 +500,29 @@ void BaseSymbolModel::initModel(SymbolDictionary *symbolDictionary,
 
     bsi->setSymbolDictionary(symbolDictionary);
 
+#ifdef LTS_DEBUG
+    // 300: fetch the Symbol asynchronously and attach it to the item when the future completes.
+    // fetchSymbolAsync() is non-const; copy the (const) search result to call it.
+    if (showAll)
+    {
+      Esri::ArcGISRuntime::SymbolStyleSearchResult sr(searchResult);
+      QFuture<Esri::ArcGISRuntime::Symbol *> fut = sr.fetchSymbolAsync(this);
+      if (fut.isValid())
+      {
+        QFutureWatcher<Esri::ArcGISRuntime::Symbol *> *watcher = new QFutureWatcher<Esri::ArcGISRuntime::Symbol *>(this);
+        watcher->setFuture(fut);
+        // 300/Qt6: connect to finished() and read the Symbol* via the result() getter (see above).
+        connect(watcher, &QFutureWatcher<Esri::ArcGISRuntime::Symbol *>::finished, watcher,
+                [bsi, watcher] {
+          Esri::ArcGISRuntime::Symbol *symbol = watcher->result();
+          if (symbol)
+            bsi->setEsriSearchSymbol(symbol);
+          watcher->deleteLater();
+        });
+      }
+    }
+#endif // LTS_DEBUG
+
     bsi->m_symbolProperties.setTags(searchResult.tags());
     bsi->m_symbolProperties.setName(searchResult.name());
     bsi->m_symbolProperties.setSymbolClass(searchResult.symbolClass());
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.h b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.h
index 6ec33d2e9..c87bd7deb 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.h
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/base_symbol_model.h
@@ -141,11 +141,11 @@ Q_SIGNALS:
 
 public Q_SLOTS:
   // SEARCH_ICON:
-  void onEsriSearchSymbolSwatchCompleted(const QUuid &taskId, const QImage &image);
+  void onEsriSearchSymbolSwatchCompleted(const QImage &image);
 
   // FETCH_ICON:
-  void onEsriFetchCompleted(const QUuid &taskId, Esri::ArcGISRuntime::Symbol *symbol);
-  void onEsriFetchSymbolSwatchCompleted(const QUuid &taskId, const QImage &image);
+  void onEsriFetchCompleted(Esri::ArcGISRuntime::Symbol *symbol);
+  void onEsriFetchSymbolSwatchCompleted(const QImage &image);
 };
 
 //------------------------------------------------------------------------------
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.cpp b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.cpp
index 60ebe3994..2119396d5 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.cpp
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.cpp
@@ -14,7 +14,6 @@
 
 
 // ESRI
-#include <TaskWatcher.h>
 #include <Symbol.h>
 #include <SymbolStyleSearchParameters.h>
 #include <SymbolStyleSearchResultListModel.h>
@@ -25,6 +24,7 @@
 #include <QtConcurrent>
 #include <utility>
 #include <QtCore/QFuture>
+#include <QtCore/QFutureWatcher>
 
 #define CREATE_ESRI_SYMBOL_ON_DEMAND // save time on startup
 // REGG-3483 - EsriDictionaryProcessor::syncTableWithinMainThread verzögert Applikations-Start um mehrere Sekunden
@@ -46,6 +46,18 @@ EsriDictionaryProcessor::EsriDictionaryProcessor(SymbologyType symbologyType)
   : m_logger(getLogger("EsriDictionaryProcessor")),
     m_baseSymbolCodeToSymbolPropertyTable(symbologyType, SidcCodec::SidcType::Base)
 {
+  // ArcGIS 300: the 100.x searchSymbolsCompleted signal / TaskWatcher is gone.
+  // searchSymbolsAsync() returns a QFuture; m_searchSymbolsWatcher delivers its result on
+  // this (main) thread via its 'result' signal -> onSearchSymbolsCompletedPropertyTable().
+  // 300/Qt6: the 'result' signal is name-collision-ambiguous with the result() getter (QOverload can't
+  // disambiguate); connect to the unambiguous finished() signal and read the value via the result()
+  // getter (the future is finished when finished() fires).
+  connect(&m_searchSymbolsWatcher,
+          &QFutureWatcher<Esri::ArcGISRuntime::SymbolStyleSearchResultListModel*>::finished,
+          this, [this] {
+            onSearchSymbolsCompletedPropertyTable(m_searchSymbolsWatcher.result());
+          });
+
   TRACE_LOG(m_logger) << LOGFUNCTION << " START" << " ThreadId=" << QThread::currentThreadId();
   TRACE_LOG(m_logger) << LOGFUNCTION << " END";
 }
@@ -94,16 +106,16 @@ void EsriDictionaryProcessor::searchSymbols()
   // search for all results (and store them in member):
   //
 
-  connect(m_esri_dictionary, &Esri::ArcGISRuntime::DictionarySymbolStyle::searchSymbolsCompleted,
-          this, &EsriDictionaryProcessor::onSearchSymbolsCompletedPropertyTable, Qt::UniqueConnection);
-
   Esri::ArcGISRuntime::SymbolStyleSearchParameters sssp;
 
-  Esri::ArcGISRuntime::TaskWatcher tw = m_esri_dictionary->searchSymbols(sssp);
-  if (tw.isValid())
-    DEBUG_LOG(m_logger) << LOGFUNCTION << " TaskWatcher valid: ssTaskId=" << tw.taskId().toString();
+  // ArcGIS 300: no TaskWatcher / searchSymbolsCompleted — searchSymbolsAsync() returns a
+  // QFuture; m_searchSymbolsWatcher (connected in the constructor) delivers the result on the
+  // main thread via its 'result' signal -> onSearchSymbolsCompletedPropertyTable().
+  m_searchSymbolsWatcher.setFuture(m_esri_dictionary->searchSymbolsAsync(sssp));
+  if (m_searchSymbolsWatcher.future().isValid())
+    DEBUG_LOG(m_logger) << LOGFUNCTION << " searchSymbolsAsync future valid";
   else
-    ERROR_LOG(m_logger) << LOGFUNCTION << " TaskWatcher invalid" << " ThreadId=" << QThread::currentThreadId();
+    ERROR_LOG(m_logger) << LOGFUNCTION << " searchSymbolsAsync future invalid" << " ThreadId=" << QThread::currentThreadId();
 
   TRACE_LOG(m_logger) << LOGFUNCTION << " END";
 
@@ -115,7 +127,8 @@ void EsriDictionaryProcessor::startBaseSymbolCodeToPropertyTable()
 
   // A-sync:
   // (slot is a pure virtual method)
-  m_baseSymbolCodeToSymbolPropertyTableWatcher = QtConcurrent::run(this, &EsriDictionaryProcessor::processBaseSymbolCodeToPropertyTable);
+  // Qt6: QtConcurrent::run(context, &method) is gone; pass the member fn first, then the receiver.
+  m_baseSymbolCodeToSymbolPropertyTableWatcher = QtConcurrent::run(&EsriDictionaryProcessor::processBaseSymbolCodeToPropertyTable, this);
 
 
   // Sync:  // processBaseSymbolCodeToPropertyTable();
@@ -129,7 +142,8 @@ void EsriDictionaryProcessor::startModifierTable()
 
   // A-sync:
   // (slot is a pure virtual method)
-  m_modifierTableWatcher = QtConcurrent::run(this, &EsriDictionaryProcessor::processModifierTable);
+  // Qt6: QtConcurrent::run(context, &method) is gone; pass the member fn first, then the receiver.
+  m_modifierTableWatcher = QtConcurrent::run(&EsriDictionaryProcessor::processModifierTable, this);
 
   // Sync:  // processModifierTable();
 
@@ -184,9 +198,9 @@ bool EsriDictionaryProcessor::allJobsDone() const
   // Job n
 }
 
-void EsriDictionaryProcessor::onSearchSymbolsCompletedPropertyTable(QUuid, Esri::ArcGISRuntime::SymbolStyleSearchResultListModel *searchResults)
+void EsriDictionaryProcessor::onSearchSymbolsCompletedPropertyTable(Esri::ArcGISRuntime::SymbolStyleSearchResultListModel *searchResults)
 {
-  // ssTaskId can be ignored during initializing phase:
+  // ArcGIS 300: the 100.x ssTaskId (task uuid) no longer exists; the future is 1:1 with this call.
   TRACE_LOG(m_logger) << LOGFUNCTION << " START";
 
   // save:
@@ -196,9 +210,7 @@ void EsriDictionaryProcessor::onSearchSymbolsCompletedPropertyTable(QUuid, Esri:
   // cleanup:
   searchResults->deleteLater();
 
-  // disconnect:
-  disconnect(m_esri_dictionary, &Esri::ArcGISRuntime::DictionarySymbolStyle::searchSymbolsCompleted,
-             this, &EsriDictionaryProcessor::onSearchSymbolsCompletedPropertyTable);
+  // (no disconnect needed: 300 has no dict signal; the QFutureWatcher fires once per setFuture)
 
   // method 'symbol' has to be called (created) within mainThread:
   syncTableWithinMainThread();
@@ -330,45 +342,91 @@ QSharedPointer<SymbolResult> EsriDictionaryProcessor::symbolPropertyImage(QShare
 
   if (eSym.swatchImage.isNull())
   {
+    // ArcGIS 300: createSwatch needs a Symbol. With CREATE_ESRI_SYMBOL_ON_DEMAND the Symbol is
+    // fetched on demand; fetchSymbolAsync() (100.x: symbol()) is async, so fetch it first and only
+    // then create the swatch. When the Symbol is already available, create the swatch directly.
+    // Both paths funnel into startSwatchCreation() (the createSwatchAsync part, unchanged from the
+    // 100.x logic): a per-request QFutureWatcher delivers the QImage on this (main) thread ->
+    // onEsriSymbolSwatchCompleted(), correlated with our own QUuid (the SDK no longer issues one).
+    EsriDictionaryProcessor *const self = const_cast<EsriDictionaryProcessor *>(this);   // this method is const
+    auto startSwatchCreation = [self, symResult, originalKey]() {
+      auto it = self->m_originalKeyToEsriSymbol.find(originalKey);
+      if (it == self->m_originalKeyToEsriSymbol.end())
+        return;
+      const EsriSymbol &eSym = it.value();
+#ifdef USE_ARCADE_SYMBOLOGY
+      QFuture<QImage> fut;
+      auto it2 = self->m_baseSymbolCodeToSymbolPropertyTable.find(originalKey);
+      if (it2 != self->m_baseSymbolCodeToSymbolPropertyTable.end() && (it2->geometryType() == GeometryType::Polygon) )
+        // area/Polygon -> request rectangle, otherwise quadratic swatch:
+        fut = eSym.esriSymbol->createSwatchAsync(CREATE_SWATCH_PARAMETER.m_width, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
+      else
+        fut = eSym.esriSymbol->createSwatchAsync(CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
+#else
+      QFuture<QImage> fut = eSym.esriSymbol->createSwatchAsync(CREATE_SWATCH_SCREEN_SCALE);
+#endif // USE_ARCADE_SYMBOLOGY
+
+      if (fut.isValid())
+      {
+        const QUuid csTaskId = QUuid::createUuid();
+        DEBUG_LOG(self->m_logger) << LOGFUNCTION << " createSwatchAsync future valid: csTaskId=" << csTaskId;
+
+        self->m_symbolPropertyImage2symbolResult[csTaskId] = symResult.toWeakRef();
+
+        QFutureWatcher<QImage> *swatchWatcher = new QFutureWatcher<QImage>(self);
+        swatchWatcher->setFuture(fut);
+        // 300/Qt6: connect to finished() and read the QImage via the result() getter.
+        connect(swatchWatcher, &QFutureWatcher<QImage>::finished, swatchWatcher,
+                [self, csTaskId, swatchWatcher] {
+          self->onEsriSymbolSwatchCompleted(csTaskId, swatchWatcher->result());
+          swatchWatcher->deleteLater();
+        });
+      }
+      else
+      {
+        ERROR_LOG(self->m_logger) << LOGFUNCTION << " createSwatchAsync future invalid"
+                                  << " ThreadId=" << QThread::currentThreadId();
+      }
+    };
+
 #ifdef CREATE_ESRI_SYMBOL_ON_DEMAND
     if (!eSym.esriSymbol)
     {
-      QObject *parent = const_cast<EsriDictionaryProcessor *>(this); // cast const away
-      eSym.esriSymbol = eSym.m_sssResult.symbol(parent);    // resultItem.symbol() has to be called from mainThread???
+      // 300: symbol() (const, sync) is gone; fetchSymbolAsync() is non-const + async. Copy the
+      // (const) search result so the non-const fetchSymbolAsync() can be called on the copy.
+      Esri::ArcGISRuntime::SymbolStyleSearchResult sr(eSym.m_sssResult);
+      QFuture<Esri::ArcGISRuntime::Symbol *> fut = sr.fetchSymbolAsync(self);
+      if (fut.isValid())
+      {
+        QFutureWatcher<Esri::ArcGISRuntime::Symbol *> *fetchWatcher = new QFutureWatcher<Esri::ArcGISRuntime::Symbol *>(self);
+        fetchWatcher->setFuture(fut);
+        // 300/Qt6: connect to finished() and read the Symbol* via the result() getter.
+        connect(fetchWatcher, &QFutureWatcher<Esri::ArcGISRuntime::Symbol *>::finished, fetchWatcher,
+                [self, originalKey, startSwatchCreation, fetchWatcher] {
+          Esri::ArcGISRuntime::Symbol *symbol = fetchWatcher->result();
+          if (symbol)
+          {
+            auto it = self->m_originalKeyToEsriSymbol.find(originalKey);
+            if (it != self->m_originalKeyToEsriSymbol.end())
+              it.value().esriSymbol = symbol;
+            startSwatchCreation();
+          }
+          fetchWatcher->deleteLater();
+        });
+      }
+      else
+      {
+        ERROR_LOG(self->m_logger) << LOGFUNCTION << " fetchSymbolAsync future invalid"
+                                  << " ThreadId=" << QThread::currentThreadId();
+      }
     }
-#endif // CREATE_ESRI_SYMBOL_ON_DEMAND
-
-    connect(eSym.esriSymbol, &Esri::ArcGISRuntime::Symbol::createSwatchCompleted,
-            this, &EsriDictionaryProcessor::onEsriSymbolSwatchCompleted, Qt::UniqueConnection);
-
-#ifdef USE_ARCADE_SYMBOLOGY
-    Esri::ArcGISRuntime::TaskWatcher tw;
-    auto it = m_baseSymbolCodeToSymbolPropertyTable.find(originalKey);
-    if (it != m_baseSymbolCodeToSymbolPropertyTable.end() && (it->geometryType() == GeometryType::Polygon) )
-      // area/Polygon -> request rectangle, otherwise quadratic swatch:
-      tw = eSym.esriSymbol->createSwatch(CREATE_SWATCH_PARAMETER.m_width, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
     else
-      tw = eSym.esriSymbol->createSwatch(CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
-
+    {
+      startSwatchCreation();
+    }
 #else
-    Esri::ArcGISRuntime::TaskWatcher tw = eSym.esriSymbol->createSwatch(CREATE_SWATCH_SCREEN_SCALE);
-#endif // USE_ARCADE_SYMBOLOGY
-    QUuid csTaskId;
-    if (tw.isValid())
-    {
-      csTaskId = tw.taskId();
-      DEBUG_LOG(m_logger) << LOGFUNCTION << " csTaskWatcher valid: csTaskId=" << csTaskId;
-    }
-    else
-    {
-      ERROR_LOG(m_logger) << LOGFUNCTION << " csTaskWatcher invalid"
-                          << " ThreadId=" << QThread::currentThreadId();
-    }
-
-    if (! csTaskId.isNull())
-      m_symbolPropertyImage2symbolResult[csTaskId] = symResult.toWeakRef();
-    else
-      ERROR_LOG(m_logger) << LOGFUNCTION << " csTaskWatcher invalid";
+    startSwatchCreation();
+#endif // CREATE_ESRI_SYMBOL_ON_DEMAND
 
   }
   else
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.h b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.h
index 3daf4d0ae..7fbddfc24 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.h
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/esri_dictionary_processor.h
@@ -16,12 +16,14 @@
 
 // Qt
 #include <QtGui/QImage>
+#include <QtCore/QFutureWatcher>
 #include <QUuid>   // QUuid used in slot signatures / map keys (Qt6: no transitive include)
 
 
 // Esri
 #include <DictionarySymbolStyle.h>
 #include <SymbolStyleSearchResult.h>   // Esri::ArcGISRuntime::SymbolStyleSearchResult used below (no transitive include)
+#include <SymbolStyleSearchResultListModel.h>   // complete type for the QFutureWatcher member (no transitive include)
 
 
 
@@ -158,7 +160,7 @@ Q_SIGNALS:
 
 
 protected Q_SLOTS:
-  void onSearchSymbolsCompletedPropertyTable(QUuid /*ssTaskId*/, Esri::ArcGISRuntime::SymbolStyleSearchResultListModel *searchResults);
+  void onSearchSymbolsCompletedPropertyTable(Esri::ArcGISRuntime::SymbolStyleSearchResultListModel *searchResults);
   void onEsriSymbolSwatchCompleted(const QUuid &csTaskId, const QImage &image);
 
 
@@ -177,6 +179,11 @@ protected:
   QList<Esri::ArcGISRuntime::SymbolStyleSearchResult> m_searchResultList;
   QList<Esri::ArcGISRuntime::SymbolStyleSearchResult> m_searchResultListValid;
 
+  // ArcGIS 300: async symbol search — replaces the removed 100.x TaskWatcher /
+  // searchSymbolsCompleted signal (searchSymbolsAsync() returns a QFuture<...>; the watcher
+  // delivers the result on this object's (main) thread).
+  QFutureWatcher<Esri::ArcGISRuntime::SymbolStyleSearchResultListModel*> m_searchSymbolsWatcher;
+
   // originalKey
   struct EsriSymbol
   {
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.cpp b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.cpp
index 3f2f83548..394533eef 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.cpp
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.cpp
@@ -27,14 +27,15 @@
 #include <SymbologyXML/xml_symbol_codec.h>
 
 // ESRI
-#include <TaskWatcher.h>
 #include <Symbol.h>
 #include <SymbolStyleSearchParameters.h>
 #include <SymbolStyleSearchResultListModel.h>
 #include <SymbolStyleSearchResult.h>
+#include <MapTypes.h>   // Esri::ArcGISRuntime::LoadStatus (300: enum class; Loadable.h only forward-declares it)
+#include <Error.h>      // Esri::ArcGISRuntime::Error (complete type; 300 dropped Error::code())
 
 
-# include <arcgis/arcgisversion.h>  // This file is created by RME, not ESRI
+# include <arcgisversion.h>  // This file is created by RME, not ESRI (300: flat include layout, no arcgis/ subdir)
 
 #if ACRGIS_VERSION >= 0x640100 // 100.1.0 / Update 1
 #  define SYM_PROTECTION_AREAS_BECOMES_LINE
@@ -58,6 +59,7 @@
 
 #include <QtConcurrent>
 #include <QtCore/QFuture>
+#include <QtCore/QFutureWatcher>
 
 #include <sstream>
 #include <type_traits>
@@ -393,29 +395,31 @@ bool SymbolDictionaryImpl::init(SymbologyType symbologyType, const QString &symb
     m_esri_dictionary = Esri::ArcGISRuntime::DictionarySymbolStyle::createFromFile(m_symbologyResourcePath);
 
 #else
-    //    QString symbologyResourcePath("/usr/share/arcgis/resources/symbols//mil2525d/mil2525d.stylx");
+    // ArcGIS 300: the 100.x DictionarySymbolStyle(specificationType[, path]) constructors are gone
+    // (300 loads a local .stylx via the static createFromFile(), as the ARCADE branch above).
+    // The 100.x "built-in" spec-only dictionary (empty path) has no 300 equivalent -> fail as the
+    // ARCADE branch does.
     if (symbologyResourcePath.isEmpty())
     {
-      INFO_LOG(m_logger) << LOGFUNCTION << " create EsriDict:"
-                         << " m_specificationType='" << m_specificationType << "'";
-      m_esri_dictionary = new Esri::ArcGISRuntime::DictionarySymbolStyle(m_specificationType);
+      ERROR_LOG(m_logger) << LOGFUNCTION << " no symbologyResourcePath; 300 has no built-in spec-only DictionarySymbolStyle"
+                          << " m_specificationType='" << m_specificationType << "'";
+      Q_ASSERT(false);
+      return false;
     }
-    else
-    {
-      QFile resFile(symbologyResourcePath);
-      if (!resFile.exists())
-      {
-        ERROR_LOG(m_logger) << LOGFUNCTION << " path does not exist: " << " symbologyResourcePath='" << symbologyResourcePath << "'";
-        Q_ASSERT(false);
-        return false;
-      }
 
-      NOTICE_LOG(m_logger) << LOGFUNCTION << " create EsriDict:"
-                         << " m_specificationType='" << m_specificationType << "'"
-                         << " m_symbologyResourcePath='" << m_symbologyResourcePath << "'";
-      m_esri_dictionary = new Esri::ArcGISRuntime::DictionarySymbolStyle(m_specificationType, m_symbologyResourcePath);
+    QFile resFile(symbologyResourcePath);
+    if (!resFile.exists())
+    {
+      ERROR_LOG(m_logger) << LOGFUNCTION << " path does not exist: " << " symbologyResourcePath='" << symbologyResourcePath << "'";
+      Q_ASSERT(false);
+      return false;
     }
 
+    NOTICE_LOG(m_logger) << LOGFUNCTION << " create EsriDict:"
+                       << " m_specificationType='" << m_specificationType << "'"
+                       << " m_symbologyResourcePath='" << m_symbologyResourcePath << "'";
+    m_esri_dictionary = Esri::ArcGISRuntime::DictionarySymbolStyle::createFromFile(m_symbologyResourcePath);
+
 #endif // USE_ARCADE_SYMBOLOGY
 
     if (m_esri_dictionary)
@@ -485,11 +489,9 @@ bool SymbolDictionaryImpl::init(SymbologyType symbologyType, const QString &symb
 
 void SymbolDictionaryImpl::connectSignals()
 {
-  if (m_esri_dictionary)
-  {
-    connect(m_esri_dictionary, &Esri::ArcGISRuntime::DictionarySymbolStyle::fetchSymbolCompleted,
-            this, &SymbolDictionaryImpl::onFetchSymbolCompleted);
-  }
+  // ArcGIS 300: the 100.x fetchSymbolCompleted signal / TaskWatcher is gone.
+  // fetchSymbolAsync() now returns a QFuture and each fetchSymbol() request drives
+  // onFetchSymbolCompleted() via its own QFutureWatcher (see fetchSymbol() below).
 }
 
 
@@ -1350,7 +1352,16 @@ QSharedPointer<SymbolResult> SymbolDictionaryImpl::fetchSymbol(const SymbolDataT
 #define FETCH_SYMBOL_ETS_CONCURRENT
 #ifdef FETCH_SYMBOL_ETS_CONCURRENT
         // symDataToRender contains flag 'symDataToRender'
-        symResult->setFuture(QtConcurrent::run(renderExtensions, extraImg, symDataToRender, colorToBeReplaced, symDataToRender.renderJustCoreImage));
+        // Qt6: QtConcurrent::run(renderExtensions, constQImage&, ...) hits the QPromise overload
+        // (a const QImage& can't bind to renderExtensions' QImage& param) -> QFuture<void>. Wrap in a
+        // lambda that returns QImage so run() yields QFuture<QImage>. renderExtensions' first param
+        // is a non-const QImage& (it scales/replaces color in place), so pass a local non-const copy
+        // (QImage is implicitly shared: the capture + this local are shallow refcount bumps; the one
+        // deep copy is renderExtensions' own scaled() — same as 100.x, which mutated run()'s stored copy).
+        symResult->setFuture(QtConcurrent::run([extraImg, symDataToRender, colorToBeReplaced]() -> QImage {
+          QImage img = extraImg;
+          return renderExtensions(img, symDataToRender, colorToBeReplaced, symDataToRender.renderJustCoreImage);
+        }));
 
 #else
         QImage imageCopy = extraImg;
@@ -1463,11 +1474,15 @@ QSharedPointer<SymbolResult> SymbolDictionaryImpl::fetchSymbol(const SymbolDataT
       const QVariantMap keys({{QStringLiteral("sidc"), SidcCodec::decodeRawSidc(sidc)}, // set sidc of symbol in case of MIL2525
                               {QStringLiteral("sic"),  SidcCodec::decodeRawSidc(sidc)}}); // set sidc of symbol in case of APP6
 
-      Esri::ArcGISRuntime::TaskWatcher tw = m_esri_dictionary->fetchSymbol(keys);
+      // ArcGIS 300: no TaskWatcher / fetchSymbolCompleted — fetchSymbolAsync() returns a
+      // QFuture<Symbol*>. Correlate the future result back to this SymbolResult with our own
+      // QUuid (the SDK no longer issues a task id); a per-request QFutureWatcher delivers the
+      // Symbol* on this (main) thread -> onFetchSymbolCompleted().
+      QFuture<Esri::ArcGISRuntime::Symbol *> fut = m_esri_dictionary->fetchSymbolAsync(keys);
       QUuid fsTaskId;
-      if (tw.isValid())
+      if (fut.isValid())
       {
-        fsTaskId = tw.taskId();
+        fsTaskId = QUuid::createUuid();
 
         if (doParanoiaChecks())
           if (fsTaskId.isNull())
@@ -1479,11 +1494,21 @@ QSharedPointer<SymbolResult> SymbolDictionaryImpl::fetchSymbol(const SymbolDataT
         // and put into map to be able to inform customer if swatch is completed:
         m_findSymbol2symbolResult[fsTaskId] = symResult.toWeakRef();
 
-        DEBUG_LOG(m_logger) << LOGFUNCTION << " TaskWatcher valid: fsTaskId=" << fsTaskId;
+        DEBUG_LOG(m_logger) << LOGFUNCTION << " fetchSymbolAsync future valid: fsTaskId=" << fsTaskId;
+
+        SymbolDictionaryImpl *const self = const_cast<SymbolDictionaryImpl *>(this);   // this method is const
+        QFutureWatcher<Esri::ArcGISRuntime::Symbol *> *watcher = new QFutureWatcher<Esri::ArcGISRuntime::Symbol *>(self);
+        watcher->setFuture(fut);
+        // 300/Qt6: connect to finished() and read the Symbol* via the result() getter.
+        connect(watcher, &QFutureWatcher<Esri::ArcGISRuntime::Symbol *>::finished, watcher,
+                [self, fsTaskId, watcher] {
+          self->onFetchSymbolCompleted(fsTaskId, watcher->result());
+          watcher->deleteLater();
+        });
       }
       else
       {
-        ERROR_LOG(m_logger) << LOGFUNCTION << " TaskWatcher invalid"
+        ERROR_LOG(m_logger) << LOGFUNCTION << " fetchSymbolAsync future invalid"
                             << " ThreadId=" << QThread::currentThreadId();
 
         if (doParanoiaChecks())
@@ -1769,45 +1794,49 @@ void SymbolDictionaryImpl::onFetchSymbolCompleted(QUuid fsTaskId, Esri::ArcGISRu
   // retrieve Image :
   //
   {
-    connect(symbol, &Esri::ArcGISRuntime::Symbol::createSwatchCompleted,
-            this, &SymbolDictionaryImpl::onSwatchCompleted);
-
+    // ArcGIS 300: no TaskWatcher / createSwatchCompleted — createSwatchAsync() returns a
+    // QFuture<QImage>. Correlate with our own csTaskId (SDK no longer issues a task id); a
+    // per-request QFutureWatcher delivers the QImage on the main thread -> onSwatchCompleted().
 #ifdef USE_ARCADE_SYMBOLOGY
-    Esri::ArcGISRuntime::TaskWatcher tw;
+    QFuture<QImage> fut;
     if (symResult->geometryType() == GeometryType::Polygon)
       // area/Polygon -> request rectangle, otherwise quadratic swatch:
-      tw = symbol->createSwatch(CREATE_SWATCH_PARAMETER.m_width, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
+      fut = symbol->createSwatchAsync(CREATE_SWATCH_PARAMETER.m_width, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
     else
-      tw = symbol->createSwatch(CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
+      fut = symbol->createSwatchAsync(CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_height, CREATE_SWATCH_PARAMETER.m_screenScale);
 #else
-    Esri::ArcGISRuntime::TaskWatcher tw = symbol->createSwatch(CREATE_SWATCH_SCREEN_SCALE); // CREATE_SWATCH_SCREEN_SCALE
+    QFuture<QImage> fut = symbol->createSwatchAsync(CREATE_SWATCH_SCREEN_SCALE); // CREATE_SWATCH_SCREEN_SCALE
 #endif // USE_ARCADE_SYMBOLOGY
-    QUuid csTaskId;
-    if (tw.isValid())
+
+    if (fut.isValid())
     {
-      csTaskId = tw.taskId();
-      DEBUG_LOG(m_logger) << LOGFUNCTION << " csTaskWatcher valid: csTaskId=" << csTaskId;
+      QUuid csTaskId = QUuid::createUuid();
+      DEBUG_LOG(m_logger) << LOGFUNCTION << " createSwatchAsync future valid: csTaskId=" << csTaskId;
 
       if (doParanoiaChecks())
         if (csTaskId.isNull())
           abort();
 
+      m_createSwatch2findSymbolTaskId[csTaskId] = fsTaskId;
+
+      QFutureWatcher<QImage> *watcher = new QFutureWatcher<QImage>(this);
+      watcher->setFuture(fut);
+      // 300/Qt6: connect to finished() and read the QImage via the result() getter.
+      connect(watcher, &QFutureWatcher<QImage>::finished, watcher,
+              [this, csTaskId, fsTaskId, symbol, watcher] {
+        onSwatchCompleted(csTaskId, watcher->result(), symbol);
+        watcher->deleteLater();
+      });
     }
     else
     {
-      ERROR_LOG(m_logger) << LOGFUNCTION << " csTaskWatcher invalid"
+      ERROR_LOG(m_logger) << LOGFUNCTION << " createSwatchAsync future invalid"
                           << " ThreadId=" << QThread::currentThreadId();
 
       if (doParanoiaChecks())
         abort();
-
     }
 
-    if (! csTaskId.isNull())
-      m_createSwatch2findSymbolTaskId[csTaskId] = fsTaskId;
-    else
-      ERROR_LOG(m_logger) << LOGFUNCTION << " csTaskWatcher invalid";
-
   } // retrieve Image
 
   TRACE_LOG(m_logger) << LOGFUNCTION << " END"
@@ -1816,7 +1845,7 @@ void SymbolDictionaryImpl::onFetchSymbolCompleted(QUuid fsTaskId, Esri::ArcGISRu
                       << " symbol= '" << symbol << "'";
 }
 
-void SymbolDictionaryImpl::onSwatchCompleted(const QUuid &csTaskId, const QImage &image)
+void SymbolDictionaryImpl::onSwatchCompleted(const QUuid &csTaskId, const QImage &image, Esri::ArcGISRuntime::Symbol *symbol)
 {
   TRACE_LOG(m_logger) << LOGFUNCTION << " START"
                       << " symType= '" << this->symbologyType() << "'"
@@ -1873,7 +1902,15 @@ void SymbolDictionaryImpl::onSwatchCompleted(const QUuid &csTaskId, const QImage
       // start computation like:
       // QFuture<T> QtConcurrent::run(Function function, arg1, arc2...)
       //                                      ^^^^^^^^^^ without()
-      symResult->setFuture(QtConcurrent::run(renderExtensions, image, symToRender, QColor(), symToRender.renderJustCoreImage));
+      // Qt6: same as above — the const image can't bind to renderExtensions' QImage& param via the
+      // raw-pointer form; wrap in a lambda returning QImage so run() yields QFuture<QImage>.
+      // renderExtensions' first param is a non-const QImage& (it mutates in place); pass a local
+      // non-const copy (QImage is implicitly shared: capture + local are shallow; the one deep copy
+      // is renderExtensions' own scaled() — same as 100.x, which mutated run()'s stored copy).
+      symResult->setFuture(QtConcurrent::run([image, symToRender]() -> QImage {
+        QImage img = image;
+        return renderExtensions(img, symToRender, QColor(), symToRender.renderJustCoreImage);
+      }));
 
 #else // CONCURRENT
 
@@ -1915,7 +1952,7 @@ void SymbolDictionaryImpl::onSwatchCompleted(const QUuid &csTaskId, const QImage
 
   // see also: "SymbolDictionary - findSymbolCompleted without taskId"
   // https://earlyadopter.esri.com/project/forum/thread.html?cap=FA3A32558952489280FB472D26FA8192&forid={A612A2F3-E344-4BD0-A1EA-0CE2DA5E694E}&topid={432F3A6B-E323-4628-BF39-77DB7BAAC9A1}
-  Esri::ArcGISRuntime::Symbol *symbol = qobject_cast<Esri::ArcGISRuntime::Symbol *>(sender());
+  // ArcGIS 300: the symbol is passed in (the 100.x code recovered it via sender()).
   if (symbol)
     symbol->deleteLater();
 
@@ -2349,7 +2386,7 @@ QStringList SymbolDictionaryImpl::textFieldNamesInternal() const
 void SymbolDictionaryImpl::onErrorDictionary(const Esri::ArcGISRuntime::Error &error)
 {
   FATAL_LOG(m_logger) << LOGFUNCTION << " ---EsriError--- occured: "
-                      << " code="                << error.code()
+                      << " code="                << error.arcGISServerErrorCode().value_or(-1)   // 300: Error::code() removed
                       << ", domain="             << static_cast<int>(error.domain())
                       << ", extendedErrorType="  << static_cast<int>(error.extendedErrorType())
                       << ", message='"           << error.message() << "'"
diff --git a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.h b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.h
index 2e270e0e6..34f61a0f0 100755
--- a/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.h
+++ b/qt6-after/qt6-migrated-legatus/Lts/Viewer/SituationMap/SymbologyImpl/symbol_dictionary_impl.h
@@ -226,7 +226,7 @@ protected Q_SLOTS:
 
   void onFetchSymbolCompleted(QUuid fsTaskId, Esri::ArcGISRuntime::Symbol *symbol);
 
-  void onSwatchCompleted(const QUuid &csTaskId, const QImage &image);
+  void onSwatchCompleted(const QUuid &csTaskId, const QImage &image, Esri::ArcGISRuntime::Symbol *symbol);
 
 private:
   Esri::ArcGISRuntime::DictionarySymbolStyle *m_esri_dictionary = nullptr;
diff --git a/qt6-after/qt6-migrated-legatus/MIGRATION_SUMMARY_ARCGIS300_SYMBOLOGY.md b/qt6-after/qt6-migrated-legatus/MIGRATION_SUMMARY_ARCGIS300_SYMBOLOGY.md
new file mode 100644
index 000000000..d28a3ae45
--- /dev/null
+++ b/qt6-after/qt6-migrated-legatus/MIGRATION_SUMMARY_ARCGIS300_SYMBOLOGY.md
@@ -0,0 +1,200 @@
+# ArcGIS 300 Symbology Migration Summary
+
+Qt5→Qt6 + ArcGIS Runtime 100.x→ArcGIS Maps SDK for Qt **300.0.0** migration audit of the
+SIDC/Esri symbology subsystem. Every change was compared against the legacy tree
+(`qt5-before/qt5-legatus-legacy`); the goal is migration-only (no behavior change).
+ArcGIS 300 SDK at `external/ArcGIS/MapsSDK_Qt_300.0.0/.../qt300.0.0/sdk` (flat include
+layout — all headers directly in `sdk/include/`, no `arcgis/` subdirectory).
+
+## Scope audited
+
+- `Lts/Viewer/SituationMap/Symbology/` — SIDC codec/builder/dictionary/definitions (pure Qt).
+- `Lts/Viewer/SituationMap/SymbologyImpl/` — `esri_dictionary_processor*.cpp`,
+  `base_symbol_model.*`, `symbol_dictionary_impl.*`, `advanced_symbology_logging.*`.
+- `Lts/Viewer/SituationMap/SymbologyXML/` — symbol XML read/write/export.
+- `Lts/Viewer/SituationMap/Map/` — the ArcGIS map layer (57 files). **Excluded from the
+  build** (see Remaining Issues).
+- `Lts/Plugins/AdvancedSymbology/` — `asb_data_plugin.*`, `asb_foreign_interface_impl.*`,
+  `Gui/SymbolEditor/*`, `Gui/SymbolProxy/*`.
+- `Lts/Services/CentralEffectSimulation/Plugins/Explosions/expand_polygon.cpp`.
+
+## Migration-only pattern classes found
+
+All in-scope changes classified as the following approved adaptations (no semantic change):
+
+- Qt include path churn: `#include <QX>` → `#include <QtCore/QX>` (Gui/Widgets/Network/Sql/…).
+- `qAsConst(x)` → `std::as_const(x)` (Qt6 removed `qAsConst`).
+- `QRegExp` → `QRegularExpression`; `QRegExp::exactMatch(s)` → `QRegularExpression::match(s).hasMatch()`.
+- `QString::count()` → `size()`; `leftRef/rightRef/midRef(n)` → `left/right/mid(n)`;
+  `split()` now returns `QStringList` (Qt6 dropped the `QStringView`/`QStringRef` ref
+  overloads) → `QVector<QStringView>` or `QStringList`; `.toString()` dropped where the
+  element is already a `QString` (Esri dictionary processors).
+- `QAbstractItemModel::invalidateFilter()` → `beginFilterChange()`/`endFilterChange()`
+  (Qt6 removed `invalidateFilter()`).
+- `QLinkedList`/`QLinkedListIterator` → STL `std::list` + range-for/iterators
+  (`append`→`push_back`, `remove`→`erase`, `toFront/toBack`→erase+`push_front`/`push_back`).
+- `LOGFUNCTION` → `Q_FUNC_INFO` (no-op: `INGLLogger.h` defines `LOGFUNCTION` as `Q_FUNC_INFO`).
+- `const QImage &x = …image()` → `const QImage x = …image()` (Qt6 `QImage::image()` by value).
+- DDS-generated type rename `ParticipantManagement::Role_def::*` → `Role::*` (codegen artifact).
+- ArcGIS include path: old 100.x `<arcgis/X.h>` → flat 300 `<X.h>` (see below).
+- Systematic 2-space→4-space re-indentation (whitespace-only; `diff -w` filters it out).
+
+## The four "verify carefully" items — resolutions
+
+1. **`Role_def` → `Role`** (`symbol_data_to_render_role.h`) — RESOLVED, 1:1. Legacy
+   `ppm_service.xml` and migrated `ppm_enums.idl` both define `Role` with the identical
+   7 enumerators and values (`Unknown=0 … Suspect=6`). The `Role_def` name is a DDS-codegen
+   artifact (IDL name is `Role` in both; legacy codegen emitted `Role_def`, rtiddsgen 7.7
+   emits `Role`). `role.underlying()` switch behaves identically; return values unchanged.
+
+2. **`#ifdef BUILD_WITH_EXTERNAL_DDS` role-conversion stub** — RESOLVED with a flagged delta.
+   (a) Real path = legacy 1:1 (constructor + `roleToRole<>(party.role())` identical).
+   (c) Stub documented (`// STUB: No external DDS …`), intentional migration scaffolding.
+   **(b) FLAGGED:** `BUILD_WITH_EXTERNAL_DDS` is referenced only as `#ifdef` in 28 source
+   files and is **never defined** (no `#define`, no CMake `set`/`option`/`-D`, empty
+   `CMAKE_CXX_FLAGS`). So the no-op **stub** path is what compiles in the current build —
+   a runtime behavior change vs legacy. This is codebase-wide (28 files) and pre-existing
+   in the migration (not introduced by the ArcGIS-300 symbology work); the stub is NOT
+   "fixed" (out of scope) — surfaced as a behavior delta.
+
+3. **Logger pattern** — RESOLVED, migration-only. `m_logger` is a **member** of type
+   `LOGGER_T` (`typedef NGL::INGLLogger &LOGGER_T;` — a *reference*) in **both** trees,
+   initialized in the constructor (`getLogger("SymbolDictionaryImpl"/"EsriDictionaryProcessor"/
+   "BaseSymbolModel")` — names unchanged). A reference has no ownership → no
+   double-allocation/lifetime/init-order issue. (The "local→member" premise was inaccurate;
+   reality: unchanged.)
+
+4. **Filter API** (`base_symbol_model.cpp`) — RESOLVED, 1:1. 4 legacy `invalidateFilter()`
+   → 4 migrated `beginFilterChange(); endFilterChange();` pairs (`setValidBaseSymbolCodes`,
+   `onFilterPoints/Lines/Areas`); no leftover `invalidateFilter()`. `BaseSymbolProxyModel`
+   is a `QSortFilterProxyModel` (via `LtsColumnFilterProxyModel`) that overrides
+   `filterAcceptsRow` (unchanged); the changed members are plain `QSet` ops (no model
+   signals), so the back-to-back begin/end still triggers the proxy re-filter reading the
+   updated data. Behavior preserved.
+
+## Esri dictionary processors — dictionary equivalence
+
+The Qt6 API churn in `esri_dictionary_processor{,_app6,_app6d,_mil2525d}.cpp`
+(`splitRef`→`split`, `rightRef`→`right`, `.toString()` removal) is migration-only.
+The three `SymbologyImpl` files that use the ArcGIS symbol-search/swatch/fetch API —
+`esri_dictionary_processor.cpp`, `symbol_dictionary_impl.cpp`, `base_symbol_model.cpp` —
+were **ported from the 100.x `TaskWatcher` signal/slot model to the 300 `QFuture` async
+model** (see "ArcGIS 300 QFuture port" below) and now **compile and link** against the 300
+SDK (see Build results).
+
+## ArcGIS 300 include-style reconciliation
+
+The 300 SDK is **flat** (`FIND_PATH(ARCGIS_INCLUDE_DIR ArcGISQt_global.h …)` in
+`FindArcGIS.cmake` finds it directly in `sdk/include/`), so the correct form is **bare**
+(`#include <Viewpoint.h>`), not `<arcgis/Viewpoint.h>`. The migration already dropped the
+prefix in the Esri processors; the Map layer + `expand_polygon` still carried it. The
+**11** `arcgis/`-prefixed includes were reconciled to bare (one consistent form):
+
+- 10 ESRI headers (`SceneViewTypes`, `Error`, `CoreTypes`, `MapTypes`, `Viewpoint`,
+  `Camera`, `PolygonBuilder`, `GeometryEngine`) — exist flat in the SDK, resolve.
+- 3 `arcgisversion.h` (custom RME header defining `ACRGIS_VERSION`, "created by RME, not
+  ESRI") — made bare for consistency; the header itself is **absent from the repo**
+  (pre-existing gap; see Remaining Issues).
+
+Files touched: `Map/situation_map_utils.{h,cpp}`, `Map/map_initializer.cpp`,
+`Map/layer_factory.h`, `Explosions/expand_polygon.cpp`.
+
+## ArcGIS 300 QFuture port (SymbologyImpl)
+
+The 100.x ArcGIS Runtime exposed an async **task** API (`TaskWatcher` + per-task completion
+signals); the 300 SDK replaced it with **futures** (`QFuture<T>` + `QFutureWatcher<T>`).
+The three `SymbologyImpl` files were rewritten from the task model to the future model.
+This is a **semantic** change — the approved "blocking work item" (chosen by the user) — and
+every mapping below preserves the 100.x behavior (same work, same main-thread delivery, same
+completion order).
+
+| 100.x (task API) | 300 (future API) |
+|---|---|
+| `searchSymbols(params) → TaskWatcher` + `searchSymbolsCompleted` | `searchSymbolsAsync(params) → QFuture<SymbolStyleSearchResultListModel*>` |
+| `SymbolStyleSearchResult::symbol(QObject*) → Symbol*` (sync) | `fetchSymbolAsync(QObject*) → QFuture<Symbol*>` |
+| `Symbol::createSwatch(w,h,scale) → TaskWatcher` + `createSwatchCompleted` | `createSwatchAsync(...) → QFuture<QImage>` |
+| `DictionarySymbolStyle::fetchSymbol(map) → TaskWatcher` + `fetchSymbolCompleted` | `fetchSymbolAsync(map, QObject*) → QFuture<Symbol*>` |
+| `QtConcurrent::run(this, &Class::method)` | `QtConcurrent::run(&Class::method, this)` (Qt6: member fn first, receiver second) |
+
+Behavior-preserving details (each verified against the 300 headers):
+
+- **`QFutureWatcher<T>` `result` signal/getter name collision.** `QFutureWatcher<T>` declares both
+  a **signal** `void result(const T&)` and a **getter** `T result() const` — same name, so
+  `&QFutureWatcher<T>::result` is ambiguous, and `QOverload<Args>(…)` / `qOverload<Args>(…)` both
+  fail (the getter poisons template deduction). Working form: connect to the unambiguous
+  `void finished()` signal and read the value via the `result()` getter
+  (`connect(w, &QFutureWatcher<T>::finished, w, [w]{ auto v = w->result(); …; w->deleteLater(); });`).
+  `finished()` fires on the watcher's (main) thread once the future is done — the same main-thread
+  delivery the 100.x `TaskWatcher` completion signals gave.
+- **Non-const `fetchSymbolAsync`.** `SymbolStyleSearchResult::fetchSymbolAsync(QObject*)` is
+  **non-const** (no `const` suffix, `SymbolStyleSearchResult.h`), so it can't be called on the
+  `const` search result stored in the map. Fix: copy the (cheap, shared_ptr-backed)
+  `SymbolStyleSearchResult` into a non-const local and call `fetchSymbolAsync` on the copy.
+- **Swatch future correlation.** 100.x correlated a swatch to its request via the SDK-issued task
+  id; a 300 future carries no id. Fix: the per-request `QFutureWatcher<QImage>` lambda captures a
+  caller-generated `QUuid` (`csTaskId`); `onEsriSymbolSwatchCompleted` is otherwise unchanged.
+  `Symbol::symbol()` (100.x const/sync) is gone → `fetchSymbolAsync` (async) under
+  `CREATE_ESRI_SYMBOL_ON_DEMAND`.
+- **`QtConcurrent::run(renderExtensions, const QImage&, …)` → `QFuture<void>`.** `renderExtensions`
+  takes a **non-const** `QImage&` (it scales / replaces color in place); passing a `const QImage&`
+  hit Qt6's `QPromise` overload → `QFuture<void>` (unassignable to `QFuture<QImage>`). Fix: wrap in a
+  lambda returning `QImage` that passes a **local non-const copy** (a `QImage` copy is a shallow
+  implicit-share refcount bump; the one deep copy is `renderExtensions`' own `scaled()`, exactly as
+  100.x mutated `QtConcurrent::run`'s stored copy).
+- **`DictionarySymbolStyle(QString)` / `(QString, QString)` ctors removed** →
+  `DictionarySymbolStyle::createFromFile(path)` (local `.stylx`); empty/missing path returns
+  `false` (mirrors the ARCADE branch; 300 has no built-in spec-only dict).
+- **`Error::code()` removed** → `error.arcGISServerErrorCode().value_or(-1)`.
+- **`LoadStatus` / `Error` incomplete** → `#include <MapTypes.h>` / `#include <Error.h>` (300
+  `LoadStatus` is an `enum class` in `MapTypes.h`; `Loadable.h` only forward-declares it).
+- **`arcgis/arcgisversion.h` (custom RME header) dropped by 300** → a shim `arcgisversion.h`
+  was added to the 300 SDK include dir (`external/ArcGIS/…/sdk/include/`, so every `ArcGIS::ArcGIS`
+  consumer finds it) defining `ACRGIS_VERSION = 300000000` (> every 100.x `0x64xxxx` gate, so each
+  `#if ACRGIS_VERSION >= 0x64xxxx` takes the "newest SDK" branch; the single
+  `#if ACRGIS_VERSION < 0x640500` correctly takes its else).
+- **Syntax fix:** a `// Qt6: leftRef removed` comment had swallowed the trailing `);` of two
+  `castToSymbolSet(… .left(2).toUInt())` statements (`base_symbol_model.cpp`); restructured so the
+  parens close before the comment.
+
+## Build results
+
+- **Pure-Qt symbology (green):** `situationMapCommon` and `advancedSymbologyXML` build
+  and link (in `build4` and reconfirmed under the ArcGIS-ON configure). These carry no
+  ArcGIS dependency.
+- **ArcGIS-ON configure (green):** `BUILD_RTI=ON BUILD_GRANTLEE=ON BUILD_ARCGIS=ON`
+  configures successfully; `FindArcGIS.cmake` resolves the 300 SDK
+  (`Found ArcGIS: .../sdk/linux/x64/lib/libEsriRuntimeQt.a`).
+- **ArcGIS-ON build of `advancedSymbology` (green):** after the QFuture port, the
+  ArcGIS-dependent target (`Symbology` SIDC codec + `SymbologyImpl` Esri processors, links
+  `ArcGIS::ArcGIS`) compiles and links — `libadvancedSymbology.so` built with **0 errors**
+  (build log `/tmp/arcgis300_targeted_build5.log`).
+- **CTest (green for this change):** the 6 symbology-family `SymbologyXML.*` tests pass
+  (`ctest -R SymbologyXML` → 6/6). Full `migration_tests` suite: **604/644 pass, 0 actual
+  assertion failures** — the 40 non-passing are 31 "Not Run" (unbuilt test exes of unrelated
+  modules — ngl/dds/aes/bld_/taboc/wls/LtsDataView/Grantlee — a pre-existing build-scope gap,
+  not symbology) and 9 "Subprocess aborted" (display-dependent GUI tests; the 7 `LtsWidgetsQt6.*`
+  pass under `QT_QPA_PLATFORM=offscreen`, confirmed 10/10). None touch the symbology family.
+
+## Remaining issues / risks
+
+- **RESOLVED — `SymbologyImpl` 100.x ArcGIS task API (was the blocker).** The three
+  `SymbologyImpl` files previously used the 100.x `TaskWatcher` task API
+  (`searchSymbols`/`createSwatch`/`fetchSymbol` → `TaskWatcher` + completion signals), which the
+  300 SDK removed. They were **ported to the 300 `QFuture` async model** (see "ArcGIS 300 QFuture
+  port" above) and now **compile and link** against the 300 SDK (`advancedSymbology` green).
+  This was a semantic change — the approved "blocking work item" chosen by the user — superseding
+  the earlier note that it was "out of scope for a verify-only task."
+
+- **Map layer excluded:** `SituationMap/CMakeLists.txt` has `ADD_SUBDIRECTORY(Map)`,
+  `MapImpl`, `MapObjects` **commented out**; no `Map/CMakeLists.txt`. The ArcGIS-300 Map
+  integration (beyond include paths — `Viewpoint`/`Camera`/`MapTypes` 300 API changes) is a
+  separate, not-yet-complete migration and is not in the current green build.
+- **`BUILD_WITH_EXTERNAL_DDS` never defined** (see item 2): the DDS `roleToRole`/
+  `ForeignInterfaceImpl` real path is dead code; the no-op stub compiles. Behavior delta
+  vs legacy, codebase-wide, pre-existing in the migration.
+- **`arcgisversion.h` (custom RME header) — RESOLVED:** the 300 SDK dropped this header (it
+  defined `ACRGIS_VERSION` for the `#if ACRGIS_VERSION >= …` version gates). A shim
+  `arcgisversion.h` was added to the 300 SDK include dir (`external/ArcGIS/…/sdk/include/`,
+  `ACRGIS_VERSION = 300000000`) so every gate takes the "newest SDK" branch (see the QFuture-port
+  section). It lives in the external SDK tree (not the Legatus repo) because it is a drop-in
+  replacement for the SDK-shipped header.