I have an Argon box which I successfully installed the 9.2.6 on. This is what I did:
1) Downloaded 9.2.6 image for RPI4
2) Removed the USB SSD bridge that connect Argon's SSD to RPI4 USB
3) Plugged in USB from my Mac to the bottom portion of the Argon case that contains SSD
4) Used Balena Etcher to write the image
5) Reconnected bridge and rebooted
And everything worked first shot.
I tried the EXACT same procedure with the nightly build LibreELEC-RPi4.arm-10.0-nightly-20210227-9c75e28 and it dies.
It rebooted 3 times and then the screen goes black. Is there another config needed somewhere?
Ok so it looks like the right hdmi port (when looking from front of box) has an issue booting on a monitor, could be an audio thing. When I booted with left HDMI it worked.