src/vs/workbench/api/common/extHostNotebookRenderers.ts/ExtHostNotebookRenderers/$postRendererMessage
class ExtHostNotebookRenderers:	public $postRendererMessage(editorId: string, rendererId: string, message: unknown): void {
		const editor = this._extHostNotebook.getEditorById(editorId);
		this._rendererMessageEmitters.get(rendererId)?.fire({ editor: editor.apiEditor, message });
	}