src/vs/workbench/services/untitled/common/untitledTextEditorModel.ts/UntitledTextEditorModel/setLanguageId
class UntitledTextEditorModel:	override setLanguageId(languageId: string): void {
		let actualLanguage: string | undefined = languageId === UntitledTextEditorModel.ACTIVE_EDITOR_LANGUAGE_ID
			? this.editorService.activeTextEditorLanguageId
			: languageId;
		this.preferredLanguageId = actualLanguage;

		if (actualLanguage) {
			super.setLanguageId(actualLanguage);
		}
	}