The crashes were due to /proc not mounted in chroot. To debug firefox (with -g) I had to mount /proc, and then firefox didn't crash anymore. Mounting /proc in chroot at boot fix the problem.
-- firefox crash with flash when libnss3-0d and libnspr4-0d are missing https://launchpad.net/bugs/94277 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs