Keep in mind that we would be very lucky if the browser developers (Firefox and Chromium devs) accept our patches upstream, even luckier if they do the porting themselves.
Out of all of them, currently the Mozilla devs accept patches for Haiku support, but they won’t port it themselves. This is the same with the WebKit devs. They mention that in this ticket (0) It would be very generous and lucky for us if PaleMoon does both the work and upstream support for their browser.
However, for Chromium-related projects, they are mostly against accepting patches or supporting OSes that are not Windows, Mac and Linux. The BSDs have lots of patches (1) to maintain but would be easier if they were upstreamed, but the Chromium guys rejected them. This almost happened with me with another tool I ported to get V8 (needed for Chromium) building on Haiku (2). In the end, they accepted them due to not introducing specific OS functionality thanks to POSIX.
As for our previous V8 port (which before was broken) was rejected even at the time passed all the tests. (3), I’ll probably ask again once all the important V8 tests pass on Haiku. I hope PaleMoon is more welcoming to at least accepting patches.