40abc0c
065d1c784268b47#diff-8a9bac13ef6264feb2b6da7c18d86b3cL733 and
40abc0c
065d1c784268b47#diff-8a9bac13ef6264feb2b6da7c18d86b3cL746 you’ll see
that the old code had a catch to deal with clean-up errors. The new
code doesn’t. This fixes that in filtering.js … whether or not there
should be a catch is a different issue.

Also, in tabs.js, I consistently get a crash when starting up my test
browser, this fixes that.