Can't get custom display resolution in 10 beta (LibreELEC-RPi4.arm-9.95.5)

I have a quirky setup whereby I'm running Kodi (booting via PINN Lite) on a Pi4 to by car's HDMI display that is 8:3 ratio with pixel dimensions 1920x720.

I use custom HDMI timing in each of the OS boot partition config.txt files thus:

hdmi_ignore_edid=0xA5000080
hdmi_timings=1920 0 88 44 148 720 0 4 5 36 0 0 0 60 0 100980000 8
hdmi_group=2
hdmi_mode=87

On LE9.2 this was working for me in that I would just get the one display resolution option of 1920x720 and the output would look great at the native resolution.

I've just tried upgrading to 9.95.5, and after putting my custom settings back in config.txt, I no longer get my special resolution option, but instead just get this:

Any idea why it's not working any more?

Thanks. Do I just move those four lines from config.txt to cmdline.txt then?

Quote from HiassofT

Try adding video=HDMI-A-1:1920x720M@60

so long,

Hias

Thanks, yes it works now using:

video=HDMI-A-1:1920x720@60

video=HDMI-A-1:1920x720M@60

video=HDMI-A-1:1920x720R@60

but using video=HDMI-A-1:1920x720MR@60 gives me no video output (that the car’s display can show at least).

Also, the refresh rate is calculated at 59.94 Hz (for all three working lines above) instead of 60 Hz, but I can’t see any side effect of that, so all good

Thanks again.