diff --git a/Core/Debugger/Debugger.cpp b/Core/Debugger/Debugger.cpp
index d7584f8a..0b8bb397 100644
--- a/Core/Debugger/Debugger.cpp
+++ b/Core/Debugger/Debugger.cpp
@@ -588,7 +588,9 @@ void Debugger::ProcessEvent(EventType type, std::optional<CpuType> cpuTypeOpt)
 			break;
 
 		case EventType::StartFrame: {
-			_emu->GetNotificationManager()->SendNotification(ConsoleNotificationType::EventViewerRefresh, (void*)evtCpuType);
+			if(!_emu->IsDebuggerBlocked()) {
+				_emu->GetNotificationManager()->SendNotification(ConsoleNotificationType::EventViewerRefresh, (void*)evtCpuType);
+			}
 			BaseEventManager* evtMgr = GetEventManager(evtCpuType);
 			if(evtMgr) {
 				evtMgr->ClearFrameEvents();
diff --git a/Core/Debugger/PpuTools.cpp b/Core/Debugger/PpuTools.cpp
index e8305b69..1c233368 100644
--- a/Core/Debugger/PpuTools.cpp
+++ b/Core/Debugger/PpuTools.cpp
@@ -403,7 +403,9 @@ void PpuTools::UpdateViewers(uint16_t scanline, uint16_t cycle)
 	for(auto updateTiming : _updateTimings) {
 		ViewerRefreshConfig cfg = updateTiming.second;
 		if(cfg.Cycle == cycle && cfg.Scanline == scanline) {
-			_emu->GetNotificationManager()->SendNotification(ConsoleNotificationType::ViewerRefresh, (void*)(uint64_t)updateTiming.first);
+			if(!_emu->IsDebuggerBlocked()) {
+				_emu->GetNotificationManager()->SendNotification(ConsoleNotificationType::ViewerRefresh, (void*)(uint64_t)updateTiming.first);
+			}
 		}
 	}
 }
diff --git a/Core/Shared/Emulator.h b/Core/Shared/Emulator.h
index d53412a0..d962bb02 100644
--- a/Core/Shared/Emulator.h
+++ b/Core/Shared/Emulator.h
@@ -180,6 +180,7 @@ public:
 	void Unlock();
 	bool IsThreadPaused();
 
+	bool IsDebuggerBlocked() { return _blockDebuggerRequestCount > 0; }
 	void SuspendDebugger(bool release);
 
 	void Serialize(ostream& out, bool includeSettings, int compressionLevel = 1);
diff --git a/UI/Debugger/ViewModels/SpriteViewerViewModel.cs b/UI/Debugger/ViewModels/SpriteViewerViewModel.cs
index eb9a8087..7b06e31c 100644
--- a/UI/Debugger/ViewModels/SpriteViewerViewModel.cs
+++ b/UI/Debugger/ViewModels/SpriteViewerViewModel.cs
@@ -528,7 +528,8 @@ namespace Mesen.Debugger.ViewModels
 					});
 				}
 
-				_coreData.Palette = DebugApi.GetPaletteInfo(CpuType);
+				DebugPaletteInfo palette = DebugApi.GetPaletteInfo(CpuType);
+				_coreData.Palette = palette.ColorCount > 0 ? palette : null;
 			}
 			RefreshTab();
 		}
diff --git a/UI/Debugger/ViewModels/TileViewerViewModel.cs b/UI/Debugger/ViewModels/TileViewerViewModel.cs
index 472599e5..767f1ed4 100644
--- a/UI/Debugger/ViewModels/TileViewerViewModel.cs
+++ b/UI/Debugger/ViewModels/TileViewerViewModel.cs
@@ -72,6 +72,7 @@ namespace Mesen.Debugger.ViewModels
 		private byte[] _coreSourceData = Array.Empty<byte>();
 		private byte[] _sourceData = Array.Empty<byte>();
 		private bool _refreshPending;
+		private bool _inGameLoaded;
 
 		[Obsolete("For designer only")]
 		public TileViewerViewModel() : this(CpuType.Snes, new PictureViewer(), null) { }
@@ -409,7 +410,9 @@ namespace Mesen.Debugger.ViewModels
 
 		private void Config_PropertyChanged(object? sender, PropertyChangedEventArgs e)
 		{
-			RefreshTab();
+			if(!_inGameLoaded) {
+				RefreshTab();
+			}
 		}
 
 		public void RefreshData()
@@ -460,7 +463,7 @@ namespace Mesen.Debugger.ViewModels
 
 		private void InternalRefreshTab()
 		{
-			if(Disposed) {
+			if(Disposed || PaletteColors.Length == 0) {
 				return;
 			}
 
@@ -650,8 +653,10 @@ namespace Mesen.Debugger.ViewModels
 		public void OnGameLoaded()
 		{
 			Dispatcher.UIThread.Post(() => {
+				_inGameLoaded = true;
 				InitForCpuType();
 				RefreshData();
+				_inGameLoaded = false;
 			});
 		}
 
diff --git a/UI/Debugger/ViewModels/TilemapViewerViewModel.cs b/UI/Debugger/ViewModels/TilemapViewerViewModel.cs
index 81a1445d..06e4a549 100644
--- a/UI/Debugger/ViewModels/TilemapViewerViewModel.cs
+++ b/UI/Debugger/ViewModels/TilemapViewerViewModel.cs
@@ -415,7 +415,9 @@ namespace Mesen.Debugger.ViewModels
 
 		private void Config_PropertyChanged(object? sender, System.ComponentModel.PropertyChangedEventArgs e)
 		{
-			RefreshTab();
+			if(!_inGameLoaded) {
+				RefreshTab();
+			}
 		}
 
 		[MemberNotNull(nameof(ViewerBitmap))]
@@ -487,7 +489,7 @@ namespace Mesen.Debugger.ViewModels
 				_coreData.CopyTo(_data);
 			}
 
-			if(_data.PpuState == null || _data.PpuToolsState == null) {
+			if(_data.PpuState == null || _data.PpuToolsState == null || _data.RgbPalette.Length == 0) {
 				_refreshPending = false;
 				return;
 			}