Use SC_AUTOCOMPLETE_DARK_MODE.

Projects/Src/CompScintEdit.pas

@@ -467,6 +467,12 @@ begin
 
     Call(SCI_SETELEMENTCOLOUR, SC_ELEMENT_LIST, FTheme.Colors[tcFore] or (SC_ALPHA_OPAQUE shl 24));
     Call(SCI_SETELEMENTCOLOUR, SC_ELEMENT_LIST_BACK, FTheme.Colors[tcBack] or (SC_ALPHA_OPAQUE shl 24));
+    var Options := Call(SCI_AUTOCGETOPTIONS, 0, 0);
+    if FTheme.Dark then
+      Options := Options or SC_AUTOCOMPLETE_DARK_MODE
+    else
+      Options := Options and not SC_AUTOCOMPLETE_DARK_MODE;
+    Call(SCI_AUTOCSETOPTIONS, Options, 0);
 
     var SelBackColor := FTheme.Colors[tcSelBack];
     Call(SCI_SETELEMENTCOLOUR, SC_ELEMENT_SELECTION_BACK, SelBackColor);

Projects/Src/IsscintInt.pas

@@ -26,6 +26,7 @@ const
   SC_CMDKEYS_DEFAULT = 0;
   SC_CMDKEYS_VSCODE_WINDOWS = 1;
   SCI_RESETALLCMDKEYS = 2812;
+  SC_AUTOCOMPLETE_DARK_MODE = 4;
 
 implementation