No Gantry modules and positions visible in Layout editor

When I update.
Grav v1.6.31
Admin Plugins v1.9.19
then
Gantry Version: 5.4.36 / Released: October 16, 2020

There is a bug when going to Gantry 5 Layout editor

Please note; the layout dropdown selection was also dissapearing.

I found that this bug also present in Gantry 5.4.35