MATE -The panel does not work, all the icons have been erased.

Clear the cache, clear all matte settings from the .config and the problem continues. I had 2 days using TW I updated it from Leap 15.3

Not sure you can upgrade from 15.3 to TW.

My TW with MATE works fine.

can you open a terminal as your user and type “mate-panel --replace”

you can try it in a console ctrl+alt+F2 (or f3 or f4 )

it didn’t work

the next thing to do is add a new user and login as that user and see if panel works.

useradd is the command and add a password to the user

sudo useradd -d /home/test_user test_user 
sudo passwd test_user

the other choice is to reinstall tumbleweed fresh.

right button on the panel -> reset all panels