Dear saen acro!
> Is your logic on vacation?
Because I'm new to this topic and only a basic unix user I'm very glad receiving suggestions from other users.
But may I ask you to stay friendly to other users which probably don't have your skill level.
> after this message, plug device
> and post result
> To be more easy for you to orientate in time use dmesg...
As posted previously no more messages are shown, let me sumarize:
[~] #
[~] # dmesg | egrep "firmware|dvb|frontend|usb" 
[    2.726867] usbcore: registered new interface driver usbfs
[    2.727859] usbcore: registered new interface driver hub
[    2.728859] usbcore: registered new device driver usb
[    9.846873] i915 0000:00:02.0: [drm] Finished loading DMC firmware i915/kbl_d                                                                                                                                                                                                mc_ver1_04.bin (v1.4)
...
[   55.449736] usbcore: registered new interface driver uvcvideo
[  669.705111] usb 1-6: new high-speed USB device number 3 using xhci_hcd
[  669.857377] [usb.001.003] /sys/devices/pci0000:00/0000:00:14.0/usb1/1-6 added   
[~] #
[~] # dmesg | egrep "firmware|dvb|frontend|usb" 
[    2.726867] usbcore: registered new interface driver usbfs
[    2.727859] usbcore: registered new interface driver hub
[    2.728859] usbcore: registered new device driver usb
[    9.846873] i915 0000:00:02.0: [drm] Finished loading DMC firmware i915/kbl_dmc_ver1_04.bin (v1.4)
...
[   55.449736] usbcore: registered new interface driver uvcvideo
[  669.705111] usb 1-6: new high-speed USB device number 3 using xhci_hcd
[  669.857377] [usb.001.003] /sys/devices/pci0000:00/0000:00:14.0/usb1/1-6 added.
[  732.898972] usb 1-6: USB disconnect, device number 3
[  732.926534] [usb.001.003] /sys/devices/pci0000:00/0000:00:14.0/usb1/1-6 removed.
[~] #
Meaning after I unplugged the device and the 'removed' message I don't get any further messages on my system 
Kernel 5.10 is a higher version number than the one with minimal requirement 5.5 so the DVB Stick should be theoretically supported
How can I make the following messages appear?
> ... dvbdev: DVB: registering new adapter and frontend ....