> The 9GB limit was not just the Rust stuff, that was for the entire docker environment with compiler, JRE, node, wasm toolkit, typescript, webpack etc.
None of this is surprising or exculpatory. Demanding >9GB of disk space to build a browser extension is insane.
> we need all of these to make a "true" reproducible build from scratch
You need and them to reproduce your build. You definitely don't need all of them to build what you're building.
You certainly are confident that you know more about GP's situation than they do.
When you took your desktop app and built a browser extension version, did you really rewrite the entire app in vanilla JavaScript just got the Mozilla review team as you seem to be expecting GP to have done? How long did it take you? What sort of opportunity cost was there from investing your time on that instead of adding value to your product?