I feel like my problem is a combination of a hardware and a software problem. As the only computer forum I’m registered too is this one, I am just posting this here.
I just installed an additional SSD in my desktop computer. It is a WD Blue 500 GB M.2 SSD. My motherboard is a MSI B450 A Pro. After installation of the M.2 SSD, Fedora (and Debian too) fail to fully boot. Fedora tells me that a timeout occured while waiting for /dev/disk/by-uuid = my new ssd’s UUID. The SSD is recognized in the UEFI without a problem.
What could be wrong?