Merge branch 'rfc822-cpu-bug' into 'gnome-3-32'
Fix 100% CPU usage on mismatch utf escapes in rfc822 string
Closes #333 (closed), #347 (closed), #299 (closed), #156 (closed), and Teams/Translation/pl#2 (closed)
See merge request !274 (merged)
(cherry picked from commit 2025aa24)
15e0d18d Fix 100% CPU usage on mismatch utf escapes in rfc822 string