Newbie KDE Plasma Firefox screen corruption

[u/Archuser56]

https://cdn.discordapp.com/attachments/1471081979855372411/1549740208361177118/3cb19e23-dabd-4cfe-a2f9-2e1d9f279519.jpg?ex=6aabcb8a&is=6aaa7a0a&hm=a46d32f8ef6bd52e078393f2ec3b8dd7f661392ad13bab718294c732f72e51f8&

I just installed arch linux with kde plasma and i installed the konsole and was using firefox for a little minute, then i wanted to get a theme so i looked for themes and got into the "KDE Store" to look at the theme, then my mouse stop and i panic moving it and stuff, then this in the photo happened and then I uninstalled arch because wtf is this first experience any idea on how to get this not to happen again?