do not restore default theme

src/vs/workbench/services/themes/browser/workbenchThemeService.ts

@@ -139,7 +139,7 @@ export class WorkbenchThemeService implements IWorkbenchThemeService {
 		// In order to avoid paint flashing for tokens, because
 		// themes are loaded asynchronously, we need to initialize
 		// a color theme document with good defaults until the theme is loaded
-		let themeData: ColorThemeData | undefined = ColorThemeData.fromStorageData(this.storageService);
+		let themeData: ColorThemeData | undefined = ColorThemeData.fromStorageData(this.storageService, isWeb);
 
 		// the preferred color scheme (high contrast, light, dark) has changed since the last start
 		const preferredColorScheme = this.getPreferredColorScheme();
@@ -496,7 +496,7 @@ export class WorkbenchThemeService implements IWorkbenchThemeService {
 
 		// remember theme data for a quick restore
 		if (newTheme.isLoaded) {
-			newTheme.toStorage(this.storageService);
+			newTheme.toStorage(this.storageService, this.settings.isDefaultColorTheme(newTheme));
 		}
 
 		return this.settings.setColorTheme(this.currentColorTheme, settingsTarget);

src/vs/workbench/services/themes/common/colorThemeData.ts

@@ -505,7 +505,7 @@ export class ColorThemeData implements IWorkbenchColorTheme {
 		this.customTokenScopeMatchers = undefined;
 	}
 
-	toStorage(storageService: IStorageService) {
+	toStorage(storageService: IStorageService, isDefaultTheme: boolean) {
 		let colorMapData: { [key: string]: string } = {};
 		for (let key in this.colorMap) {
 			colorMapData[key] = Color.Format.CSS.formatHexA(this.colorMap[key], true);
@@ -515,12 +515,13 @@ export class ColorThemeData implements IWorkbenchColorTheme {
 			id: this.id,
 			label: this.label,
 			settingsId: this.settingsId,
-			themeTokenColors: this.themeTokenColors.map(tc => ({ settings: tc.settings, scope: tc.scope })), // don't pesist names
+			themeTokenColors: this.themeTokenColors.map(tc => ({ settings: tc.settings, scope: tc.scope })), // don't persist names
 			semanticTokenRules: this.semanticTokenRules.map(SemanticTokenRule.toJSONObject),
 			extensionData: ExtensionData.toJSONObject(this.extensionData),
 			themeSemanticHighlighting: this.themeSemanticHighlighting,
 			colorMap: colorMapData,
-			watch: this.watch
+			watch: this.watch,
+			isDefaultTheme
 		});
 
 		// roam persisted color theme colors. Don't enable for icons as they contain references to fonts and images.
@@ -570,12 +571,14 @@ export class ColorThemeData implements IWorkbenchColorTheme {
 		return themeData;
 	}
 
-	static fromStorageData(storageService: IStorageService): ColorThemeData | undefined {
+	static fromStorageData(storageService: IStorageService, doNotRestoreDefaultTheme: boolean): ColorThemeData | undefined {
 		const input = storageService.get(ColorThemeData.STORAGE_KEY, StorageScope.GLOBAL);
 		if (!input) {
 			return undefined;
 		}
 		try {
+			let isDefaultTheme = false;
+
 			let data = JSON.parse(input);
 			let theme = new ColorThemeData('', '', '');
 			for (let key in data) {
@@ -607,9 +610,12 @@ export class ColorThemeData implements IWorkbenchColorTheme {
 					case 'extensionData':
 						theme.extensionData = ExtensionData.fromJSONObject(data.extensionData);
 						break;
+					case 'isDefaultTheme':
+						isDefaultTheme = data.isDefaultTheme;
+						break;
 				}
 			}
-			if (!theme.id || !theme.settingsId) {
+			if (!theme.id || !theme.settingsId || doNotRestoreDefaultTheme && isDefaultTheme) {
 				return undefined;
 			}
 			return theme;

src/vs/workbench/services/themes/common/themeConfiguration.ts

@@ -308,6 +308,11 @@ export class ThemeConfiguration {
 		return theme;
 	}
 
+	public isDefaultColorTheme(theme: IWorkbenchColorTheme): boolean {
+		let settings = this.configurationService.inspect(ThemeSettings.COLOR_THEME);
+		return settings && settings.default?.value === theme.settingsId;
+	}
+
 	public findAutoConfigurationTarget(key: string) {
 		let settings = this.configurationService.inspect(key);
 		if (!types.isUndefined(settings.workspaceFolderValue)) {