All the pre-installed, 'native MATE', programs have suddenly lost their menu bars. And so have some, maybe all, of the programs I've installed.
The other day I had been using EoM and a little later when I went to use it again it opened with no menu bar. I thought it was a problem with EoM and spent an awful lot of time trying to attack the problem with that idea in mind. Eventually noticed the menu bar was missing as well in Pluma which lead me to find that the menu bars were missing on all MATE's programs and at least a couple I'd installed. Makes them very difficult, some nearly impossible, to use.
Currently I'm thinking that somewhere there must be a configuration option that some how got changed. I can't figure how as between the two above mentioned uses of EoM, the only thing I can remember doing is trying some changes to Panel and Plank.
For all my searching and reading and poking around my system, I can't find anything that even hints at what the problem might be. But I still suspect it will turn out to be something simple, maybe even obvious.
In the mean time, what am I to do?