Fairly fresh install of MATE 18.04 in MBP '09 . . . overall working well, but lately noticing that the bottom panel will “flicker” when scrolling down through some web page, or, also as a web page is loading . . . once the page has loaded the flickering stops . . . . Seemed like if more than one app is loaded and showing in the panel the problem is “less” . . . . It’s not a show stopper, but, somewhat irritating . . . .
I saw another thread entitled “Panel flickering” in 16.04, and I read through it, some of the posters were mentioning “window compositor” in MATE Tweaks . . . but I couldn’t exactly figure out what they wanted the OP to do with it . . . . Funny, problem is “happening” now as I’m typing this post . . . each key stroke makes the panel “shake” . . . .
Window Manager is set to "Marco (adaptive compositor) . . . which is possibly the default, I don’t think I changed it or set it . . . should I just pick another one and see what happens?
Even “funnier” now while I’m typing the panel is not shaking . . . so problem seems to come and go???