> enabling this in Sway results in some very odd behavior that breaks certain things
I've been using Firefox Nightly in Wayfire (also wlroots based) with GL (and even WebRender) for quite a long time now, it works very well, about the only issue left is popover placement is odd occasionally. What issues do you have?
With hw rendering enabled, opening a single Firefox window and browsing works fine. However when I try to open a new window the browser and desktop immediately become incredibly laggy and eventually unresponsive. I think I was able to successfully open a different tty and kill Firefox, which then fixed the issue, but it repro'd every time. Open one Firefox window, everythings fine. Open two, things slow to a crawl.
I'm surprised you were able to get WebRender working as well, I think I recall Firefox instantly crashing when I tried that. This was a few weeks ago.
I've been using Firefox Nightly in Wayfire (also wlroots based) with GL (and even WebRender) for quite a long time now, it works very well, about the only issue left is popover placement is odd occasionally. What issues do you have?