Thanks for all the info so far, but I will now try to just install archlinux for arm, which has some 905 support and the accelerated X11 drivers, and chromium and firefox and all that. Not sure how fiddly it is, but nothing can be worse at this point.
Its nice that Kodi runs straight out of the box with LibreELEC and its surprising how well and easy it all is ... I was really happy.
But its just like owning this new Ferrari that was designed without a gearbox. Eventually you will want a manually driven car to have a gearbox. Its just not working out any other way.
I have been cross-compiling stuff since a week now, and I still got no browser running. Its just one dead end after another.
The chromium-elec docker doesn't work, because the amlogic build has the v3 kernel ... the way docker works is to pull in binaries from other distros (raspian), and you basically end up with just that, a giant 500MB static binary clobbered thing that you can run inside the existing OS ... but since xorg needs direct hardware access with zero isolation/virtualization involved, it also needs a certain degree of kernel compatibility for the driver. So that means I would need to either source a very very old distro with v3 kernel which only has extremely outdated browser versions ... or change the build to v4 kernel (Amlogic explicitly uses v3 .. I suppose that straight up breaks all kinds of things), or try my luck cross-compiling chromium from scratch ... which should take another week at least.
I have had it with compiling for now.
Let's go beloved Arch Linux ARM