They do, well at least Chrome does: https://blog.chromium.org/2015/03/new-javascript-techniques-for-rapid.html https://blog.chromium.org/2015/03/new-javascript-

They do, well at least Chrome does: https://blog.chromium.org/2015/03/new-javascript-techniques-for-rapid.html https://blog.chromium.org/2015/03/new-javascript-techniques-... > Chrome 42 introduces an advanced technique of storing a local copy of the compiled code, so that when the user returns to the page the downloading, parsing, and compiling steps can all be skipped. Not sure what's going on in Google Cloud UI, though. It's a dumpster fire.