src/vs/editor/browser/services/abstractCodeEditorService.ts/AbstractCodeEditorService/openCodeEditor
class AbstractCodeEditorService:	async openCodeEditor(input: IResourceEditorInput, source: ICodeEditor | null, sideBySide?: boolean): Promise<ICodeEditor | null> {
		for (const handler of this._codeEditorOpenHandlers) {
			const candidate = await handler(input, source, sideBySide);
			if (candidate !== null) {
				return candidate;
			}
		}
		return null;
	}