src/vs/workbench/services/extensions/browser/webWorkerExtensionHost.ts/WebWorkerExtensionHost/_getWebWorkerExtensionHostIframeSrc
class WebWorkerExtensionHost:	private async _getWebWorkerExtensionHostIframeSrc(): Promise<string> {
		const suffixSearchParams = new URLSearchParams();
		if (this._environmentService.debugExtensionHost && this._environmentService.debugRenderer) {
			suffixSearchParams.set('debugged', '1');
		}
		COI.addSearchParam(suffixSearchParams, true, true);

		const suffix = `?${suffixSearchParams.toString()}`;

		const iframeModulePath = 'vs/workbench/services/extensions/worker/webWorkerExtensionHostIframe.html';
		if (platform.isWeb) {
			const webEndpointUrlTemplate = this._productService.webEndpointUrlTemplate;
			const commit = this._productService.commit;
			const quality = this._productService.quality;
			if (webEndpointUrlTemplate && commit && quality) {
				// Try to keep the web worker extension host iframe origin stable by storing it in workspace storage
				const key = 'webWorkerExtensionHostIframeStableOriginUUID';
				let stableOriginUUID = this._storageService.get(key, StorageScope.WORKSPACE);
				if (typeof stableOriginUUID === 'undefined') {
					stableOriginUUID = generateUuid();
					this._storageService.store(key, stableOriginUUID, StorageScope.WORKSPACE, StorageTarget.MACHINE);
				}
				const hash = await parentOriginHash(window.origin, stableOriginUUID);
				const baseUrl = (
					webEndpointUrlTemplate
						.replace('{{uuid}}', `v--${hash}`) // using `v--` as a marker to require `parentOrigin`/`salt` verification
						.replace('{{commit}}', commit)
						.replace('{{quality}}', quality)
				);

				const res = new URL(`${baseUrl}/out/${iframeModulePath}${suffix}`);
				res.searchParams.set('parentOrigin', window.origin);
				res.searchParams.set('salt', stableOriginUUID);
				return res.toString();
			}

			console.warn(`The web worker extension host is started in a same-origin iframe!`);
		}

		const relativeExtensionHostIframeSrc = FileAccess.asBrowserUri(iframeModulePath);
		return `${relativeExtensionHostIframeSrc.toString(true)}${suffix}`;
	}