I have a weird "bug" that seems to happen at random. In some files, even simple ones that evaluate fine at first, the auto-completion boxes get blacked out after a few evaluations. The lines of the completion box are still valid, just blacked out: for example, if I go blindly down two levels with the keyboard then hit enter, the 2nd entry of the completion list will be pasted in the notebook.
Here is a screen capture of the problem: after 32 evaluations in a notebook that contained only the two cells shown (I was playing around options), the auto-completion for "ColorFunction" opens a black box. From then on, all other auto-completion will be blacked out.
The only fix I know is to save, quit Mathematica and relaunch the file. It will then usually work fine for a while until it does not, sometimes only after a few evaluations... It is not crucial but I find it very annoying. Should I report-it as a bug or is the problem on my side ?
And even better, any ideas on how to fix this ? Thanks !
I am running 18.104.22.168 on MacOS 10.12.6 (Sierra), but I had this problem lingering on for quite a while, across Mathematica and OS updates.