Today's automatic upgrade went fine - no issues now with Malwarebytes.
Now also installed on Desktop, following notification of discontinuation of ISTP.
Installation was a little slower than ISTP, and once again required the removal of MBAM, which has been raised with the Beta team. MBAM reinstalled after FSPTP.
Although I much prefer this colour scheme to that of the previous ISTP, I would personally prefer the systray icon to be a little larger, without the black background. Given that the desktop icon doesn't have the black background, I'm not sure what the purpose of it is on the smaller systray icon, and in my opinion, it looks better without it (see image with 'customised' icon).
The black background is just a workaround to make it look correct in white tray background. Otherwise the borders of the "screens", that are white, would be lost to the background. I guess another way would be to just have a black single-pixel border around the icon.
I just tested changing desktop background to solid white and the desktop icon has this problem.