when upgrading emacs 29.4 to 30.1 my plugins didn't work anymore, starting with corfu-global-mode giving error symbol definition void.
this minad/corfu#412 (comment) link finally gave the right impulse just that I installed all packages anew doing M-x list-packages and there reinstalling every package I use including use-package.
also, even when on the plus side of news, on windows I only need one LNK-File to start a emacs daemon automatically with emacsclient anymore: "C:\Program Files\Emacs\emacs-30.1\bin\emacsclientw.exe" -c -a "" starting in "C:\Program Files\Emacs\emacs-30.1\bin"