bucket

make sure that the launcher is closed when you delete the file as it will automatically readd it

If you installed the minecraft launcher with yay or the deb you can use the script below as a temporary fix, create a file like minecraftlauncherfix.sh and open it in a text editor, then paste in the script below into it. since i dont think that you can pin scripts to the task bar in any DE putting it in the desktop folder should work out.

i hope this helps anybody

#!/bin/bash
file=~/.minecraft/webcache2/Default/Preferences
if [ -e "$file" ]; then
    echo "Problematic file exists, removing it"
    rm $file
else
    echo "Problematic file does not exist"
fi

minecraft-launcher

deleting

.minecraft/webcache2/Default/Preferences

fixes the error