src/vs/workbench/browser/parts/views/treeView.ts/CustomTreeView/activate
class CustomTreeView:	protected activate() {
		if (!this.activated) {
			type ExtensionViewTelemetry = {
				extensionId: string;
				id: string;
			};
			type ExtensionViewTelemetryMeta = {
				extensionId: { classification: 'SystemMetaData'; purpose: 'FeatureInsight'; comment: 'Id of the extension' };
				id: { classification: 'SystemMetaData'; purpose: 'FeatureInsight'; comment: 'Id of the view' };
				owner: 'digitarald';
				comment: 'Helps to gain insights on what extension contributed views are most popular';
			};
			this.telemetryService.publicLog2<ExtensionViewTelemetry, ExtensionViewTelemetryMeta>('Extension:ViewActivate', {
				extensionId: this.extensionId,
				id: this.id,
			});
			this.createTree();
			this.progressService.withProgress({ location: this.id }, () => this.extensionService.activateByEvent(`onView:${this.id}`))
				.then(() => timeout(2000))
				.then(() => {
					this.updateMessage();
				});
			this.activated = true;
		}
	}