If you’re encountering the “Device is active” pop-up error while installing Fedora Linux, it indicates that the target device for installation is currently in use.
In my situation, the drive I intended to install Fedora on was encrypted. Since I didn’t have any important data on it, I simply formatted the device using the GNOME Disks utility on my Debian desktop PC.

This resolved the issue. Therefore, if you face the same problem during Fedora installation:
JUST try formatting the drive before starting the process. This issue might also occur with other Linux distributions!
Device is active - pop up error.
> I suggest you to use a single dedicated hdd or ssd for new fresh install, format it, make it clean so you can use it easier during the installation process, and just use/follow auto disk formating.
Device: Lenovo Thinkpad T480S
M.2 Sata WDC. as targeted drive for my Fedora 41.
I dual bootong with Windows 11, each OS use a dedicated drive (so i use 2 drives).
Good luck guys!