Issue description

Using the new game mode with the window inside the ide, if I use the stretch mode to fill the inner window, tha camera does not frame with zoom to the group correctly, or jump on Y when changing to other camera. Seems related to the new window size not matching the window size defined in the project window size. If I change the window size to match the project defined size, it all work just fine. It's a dynamic window size problem.

Steps to reproduce

1.Define 800x600 window size in the project settings
2. Use the new ide game inner window to run the project, and stretch to fill.

(Optional) Minimal reproduction project

camtest.zip