easiest way to test this is using console command “setRes xwf”.
or in c++
FSystemResolution::RequestResolutionChange(, , EWindowMode::WindowedFullscreen);
This work fine in 4.5.1 and broken since 4.6 (I’ve tested this with 4.6.1 and 4.7.2)
There was another topic about this already.
I created this one since old one was marked as resolved.
Thanks for your report! Please take this information and copy it to original post you found ( Borderless window mode broken in 4.6 - Programming & Scripting - Epic Developer Community Forums ) so we can address issue there.
“Resolved” state only means that an answer has been accepted, but you can always comment if post hasn’t been “Closed” and it will remove Resolved status.