src/vs/workbench/contrib/extensions/browser/extensionsWorkbenchService.ts/Extensions/local
class Extensions:	get local(): IExtension[] {
		const installing = this.installing
			.filter(e => !this.installed.some(installed => areSameExtensions(installed.identifier, e.identifier)))
			.map(e => e);

		return [...this.installed, ...installing];
	}