When creating a new skin using File > New skin, I am unable to select the color that the new model will be when in fillscreen mode. The color selector looks to be stuck in the background, as it is covered by the dark overlay. Clicking the color selector does nothing. Clicking the box next to "model color" results in the color selector flashing once, and it will not flash again until the page is reloaded.

When doing the same thing in fullscreen, the new skin dialog box does not even display.

Here is a video of this happening - https://www.youtube.com/watch?v=rcPnHwGazhA

Using Firefox 68.0.1 and PMCSkin3D version v8.156112 Beta. uBlock Origin was disabled.