HiassofT you are right that I have changed the resolution to 1360x768 afterward I reached the GUI. It was a test if the resolution was saved and known after the reboot.
LibreELEC-RPi4.arm-10.0-devel-20211107115829-035c5c6.tar uploaded directly to the .update folder on the card. Then inserted and RPi4B turned on. Again the rainbow cube appeared, then black screen (TV doesn't appear "No signal" as always), on the TV I selected HDMI1 and back to HDMI3 and seen the extracting process with LibreELEC logo. Still the same issue.
Output with drm.debug=0x04:
Output with drm.debug=0x04 video=HDMI-A-1:1360x768M@60D after reboot: