As in bug#10053 a /etc/mtab~ file causes boot to fail when remounting / in rw mode. Depending on the version in line 218 or 221 of rc.sysinit. This is with initscripts-4.63-1 and initscripts-4.70-1 Perhaps the fix applied to Rawhide in initscripts-4.97 should be applied
fixed in the current initscripts...