src/vs/workbench/browser/parts/editor/editorGroupView.ts/EditorGroupView/onDidChangeEditorPartOptions
class EditorGroupView:	private onDidChangeEditorPartOptions(event: IEditorPartOptionsChangeEvent): void {

		// Title container
		this.updateTitleContainer();

		// Title control Switch between showing tabs <=> not showing tabs
		if (event.oldPartOptions.showTabs !== event.newPartOptions.showTabs) {

			// Recreate title control
			this.createTitleAreaControl();

			// Re-layout
			this.relayout();

			// Ensure to show active editor if any
			if (this.model.activeEditor) {
				this.titleAreaControl.openEditor(this.model.activeEditor);
			}
		}

		// Just update title control
		else {
			this.titleAreaControl.updateOptions(event.oldPartOptions, event.newPartOptions);
		}

		// Styles
		this.updateStyles();

		// Pin preview editor once user disables preview
		if (event.oldPartOptions.enablePreview && !event.newPartOptions.enablePreview) {
			if (this.model.previewEditor) {
				this.pinEditor(this.model.previewEditor);
			}
		}
	}