FF's apparmor profile shipped with 51.0.1 contains a line
deny @{HOME}/.local/share/recently-used.xbel r,
which leads to this issue.
I removed the line in a patch named "VERSION 6" provided at https://bugs.launchpad.net/bugs/1659988
That said, this issue - is 100% related to the firefox package (which contains that profile - not related to apparmor itself
FF's apparmor profile shipped with 51.0.1 contains a line
deny @{HOME} /.local/ share/recently- used.xbel r,
which leads to this issue.
I removed the line in a patch named "VERSION 6" provided at https:/ /bugs.launchpad .net/bugs/ 1659988
That said, this issue
- is 100% related to the firefox package (which contains that profile
- not related to apparmor itself