When konsole launches, it should launch your default shell…
The first issue might be your zsh configuration files - if you create a new USER you should get a default shell - try that.
So the first ones usually are .zshrc, xzprofile and so you could try running zsh from krunner with the -f option.
zsh -f
You can try switching to TTY and run echo $SHELL and set it with chsh… worth checking?
First, make sure the shell isn’t running in your blank window 1. type echo Hello and hit Enter.
2. Run zsh -f
3. MOve the config files to isolate the issue… move ~/.zshrc ~/zshrcBLANK, maybe also ~/.zshenv
4. restart konsole/yakuake and if the prompt appears, reintroduce/copy back contents of the originals until you figure it out.
To check the config, try zsh -x for debug.
Set zsh with:
chsh -s $(which zsh)
Try to create a basic prompt in the black window with:
PROMPT='%n@%m %~ %# '