Why Do Recent Releases of Writer Still Have Mac Display Problems?

I’ve had problems with Libre Office Writer display on my 2017 iMac (Retina 4K 21.5") for several years. The only useable version I’ve found is 6.1.3.1. But it still has odd artifacts in the display:

Writer 6.1.3.1

I keep trying new versions when they come out, but the garbage on the display is never fixed.

Here’s what happens with 6.4.0.3

No amount of tweaking the settings can fix this. Sometimes, scrolling will cause a window redraw which fixes it for a while, but the screen garbage always comes back.

Both of the above screenshots are of the same document which was created on an MBA running version 6.2.2.2. (That version works for my wife on her 2015 MBA running Catalina, but wouldn’t work for me on my 2017 iMac. Based on my bad experience with recent versions, my wife has decided not to upgrade.)

For me, the only recent useable version is 6.1.3.1. That’s the only solution I"ve found.

You can try to use a fresh user profile and see, if it helps. This often breaks LO, if the profile is old and shared for multiple LO versions: LibreOffice user profile - The Document Foundation Wiki

Yep. That seems to have done it. I just deleted the old profile. The only thing I had put in it myself was my name. I created a new profile. The screen garbage seems to be gone.

jmux provided what seems to be the answer. Get rid of the old profile and create a new one.