Dead keys not working for KDE applications using Portuguese Keyboard

Hello, I am using Arch Linux with KDE installed and I can't use any of my dead accent keys on qt applications.

I use a Portuguese (Portugal) keyboard, which contains a special cedilla key "ç" which works perfectly well. However the dead "´" and "~" keys dont do anything in kde applications.

The keyboard layout is correct because non qt applications (such as Chromium and Code) work perfectly well. This is clearly either a qt or a kde bug and not a keyboard problem. Though I'm more inclined to it being a qt bug because non KDE apps also suffer the same problem.

I used xev on the Konsole and it detects the key perfectly, the program even correctly detects the character and knows that it's a dead key. On KDE settings, the keyboard is correctly setup as a Portuguese keyboard with dead keys. I know this is a recurrent bug, but all previous closed issues don't solve anything. Even the arch forums dont solve the problem.

Can anyone help me?

Kernel Version: 5.4.13-arch1-1

KDE Version: 5.17.5