What's going on with installation manager?

I am on beta 1.37.8.0
Noted this recently. After launching MSFS in full screen mode and after “Checking for updates” page I’m getting this screen for a fraction of a second then sim continues loading in windowed mode. “Checking for updates” page took about 3 sec before but now it’s around 20-25.
Sim continues loading normally but in windowed mode. So I switch it back to full screen.

What is it?

Hi @WindlessBulb411,

We’ve moved your topic to the Sim Update 15 Beta category since your are under SU15B.

This issue has been reported here:

Closing this post because it is a duplicate. If you experience this issue, please participate in the thread that @DementedCorn327 has posted above.