Different people report slightly different versions of the problem, but for me it was only ever with documents based on one specific template. It was downloaded from a company I was sort of doing some work with at the time, and you were required to use that
template to generate certain documents they needed.
From online conversations I had in various back channels, I definitely was not the only person who had this problem with that template, yet it's equally clear not everyone did. No-one could figure out any obvious factor that all and only the people having
the problem had in common, but as far as I know it was never looked into with any real rigour.
I went here back then (probably like two years ago now) hoping it was a known issue, but apparently it isn't. Seems it's just common enough that you can find other people in the same situation if you look, but not common enough for MS or anyone else I've
found to have a diagnosis, much less a solution.
I'm not sure I still have the template so I can't speak with authority on safe mode. If no-one else speaks up, I'm home sick and might have some time on my hands to try that in the next day or two.