After last restart forum has been up almost 2 days without crash, no plugin has been disabled. Actually I didn't do anything else, just started NodeBB again.
I was crating bug to GitHub, but thought that this could be know issue, after upgrade, so thats why added this question first... I did se you managed to do it fist, so I added information to there. I use tags, both 1.4.5 and 1.4.6 has this issue.
So I'n my opinion it is bug that it ignores categories for some people. How to delete those entries in MongoDB?