There are a lot of similar issues with different external displays/TV. My issue is with the official 7" RPI touchscreen.
With LE9x works good, after upgrade to 10.0.2 (via ssh) the display shows only rainbow square upon boot. After it only the black/white raster.
In my setup there is no hdmi, no external displays, only the 7" touchscreen.
Logfile is here: http://ix.io/3USN. Can't activate debug mode using navigation, having only ssh access.
Thanks Boris