Update: It's not all that broken it seems. Not all accelerators don't work, only some of them. Of course at first I precisely happened to want the ones that didn't work, hence I assumed none of them worked... but it's not that bad.
What doesn't work: Control + F6, Control + F7, Control + F8, Control + F12.
These shortcuts are not used by Gnome or anything, so they should be available, no idea what's wrong.
Update: It's not all that broken it seems. Not all accelerators don't work, only some of them. Of course at first I precisely happened to want the ones that didn't work, hence I assumed none of them worked... but it's not that bad.
What doesn't work: Control + F6, Control + F7, Control + F8, Control + F12.
These shortcuts are not used by Gnome or anything, so they should be available, no idea what's wrong.