ui element selection (#246643)

* ui element selection window hack

* add background

* target simple browser

* revert to non-simple browser attempt

* some saucy stuff

* saucy cleanup

* some additions:

* add better button, better listening, even saucier

* move to css and also make sure not to block elements during screenshot

* it's even saucier now

* remove browser id lookup

* fix merge conflicts and clean up

* make timeout 3 seconds

* some cleanup

* remove computed css

* use built in button instead

* address many comments :)

extensions/simple-browser/preview-src/index.ts

@@ -95,6 +95,8 @@ onceDocumentLoaded(() => {
 
 			// Try to bust the cache for the iframe
 			// There does not appear to be any way to reliably do this except modifying the url
+			const existing = new URLSearchParams(location.search);
+			url.searchParams.append('id', existing.get('id')!);
 			url.searchParams.append('vscodeBrowserReqId', Date.now().toString());
 
 			iframe.src = url.toString();