src/vs/workbench/api/browser/mainThreadProfilContentHandlers.ts/MainThreadProfileContentHandlers/$registerProfileContentHandler
class MainThreadProfileContentHandlers:	async $registerProfileContentHandler(id: string, name: string, extensionId: string): Promise<void> {
		this.registeredHandlers.set(id, this.userDataProfileImportExportService.registerProfileContentHandler(id, {
			name,
			extensionId,
			saveProfile: async (name: string, content: string, token: CancellationToken) => {
				const result = await this.proxy.$saveProfile(id, name, content, token);
				return result ? URI.revive(result) : null;
			},
			readProfile: async (uri: URI, token: CancellationToken) => {
				return this.proxy.$readProfile(id, uri, token);
			},
		}));
	}