Anyone having major issues with Fedora 39?

If you want a smooth transition, then consider waiting a couple of weeks to a month. And if you're on one of the 'immutable' spins, you can just try it and rebase back to Fedora 38 if you don't like what you see.

Nothing serious. In GNOME my alternate chars and compose were set to the same key after the upgrade; just had to change one. There was an issue with "sloppy" window focus, but they fixed that upstream before the official release of 45. I upgraded during the beta.

Fedora 39 KDE Wayland issues with new Nvidia GPU. X11 no issues

I noticed some shortcuts for window navigation don't work properly. For example, "View split on left" (Shift+Super+H on my machine) doesn't work if the target window is receiving text input. It seems that killing ibus temporary solves the issue, so beware if you're using ibus.

Nothing wrong for me, it was a pretty tame release and went smoothly