A race condition seemed to exist between tab destruction and un-registering a ResizeObserver resulting in a null deref crash.
The original reporter in Forum Topic 25311 experienced this on msn.com so that was the functional test reference.
Since these are just interpreted comments, there's 0 impact on actual code.
This removes all lines that match /* vim: set(.*)tw=80: */ with S&R -- there are
a few others scattered around which will be removed manually in a second part.