I don’t like bash, so I use fish. If I set my login shell to fish using chsh, SDDM is unable to start Plasma when I restart the computer, but if I change TTY by pressing Ctrl+Alt+F3 & use startplasma-wayland it works fine even in fish. If I do chsh again & change my shell back to bash, SDDM begins working fine again after a restart. I have the same setup with Plasma as my desktop & my login shell set to fish on other distros & SDDM has no issues starting Plasma on those. Something is different in Fedora that causes it to fail if the login shell is not bash, or at least it fails if it’s fish. It took a few hours to figure this out, & I finally found other mentions of this problem. I found a thread on discuss.kde.org about this, & I have written my own thread about it too. I’m not sure where to file a bug report about this or what other information to gather, but I’m willing to provide any information asked for. My workaround right now is to keep my shell as bash, or set it to fish like I want but put an if statement in my ~/.config/fish/config.fish to read $XDG_SESSION_TYPE & run startplasma-wayland if it’s equal to “tty”.