Comment 0 for bug 1838508

This appears to be a rather recent regression. I started observing this about a month ago (beginning of July 2019), and it was recently reported by another user (https://discourse.ubuntu.com/t/call-for-testing-chromium-browser-deb-to-snap-transition/11179/95).

Steps to reproduce:

0) Make sure the chromium snap is your default browser
1) Open the chromium snap, and do your usual browsing activities
2) Open a terminal, and execute `xdg-open https://example.org`
2b) Repeat step 2 a few times until you get a notification that chromium crashed, offering to restore the previous session

When the crash happens, I'm seeing this relevant error:

[ERROR:process_singleton_posix.cc(207)] read() failed: Permission denied (13)

and the corresponding entries in journalctl:

juil. 31 09:53:07 bribon audit[25535]: AVC apparmor="DENIED" operation="file_perm" profile="snap.chromium.chromium" name="/run/user/1000/snap.chromium/.org.chromium.Chromium.LWcyoF/SingletonSocket" pid=25535 comm="chrome" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0
juil. 31 09:53:07 bribon audit[25535]: AVC apparmor="DENIED" operation="file_perm" profile="snap.chromium.chromium" name="/run/user/1000/snap.chromium/.org.chromium.Chromium.LWcyoF/SingletonSocket" pid=25535 comm="chrome" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0