[bug]: No header on Linux so I can't move the window

[PumpkinSeed]

Describe the bug
I downloaded the Firecamp 3.3.0 AppImage and run it from my terminal like:

chmod +x Firecamp-3.3.0-beta.3.x86_64.AppImage
./Firecamp-3.3.0-beta.3.x86_64.AppImage

The desktop application doesn't have a header bar, so I can't move the application or minimize or anything I can do by using the header. I wanted to move it from one display to another, but I couldn't do it.

Expected behavior
I can grab it by the header and move it around.

Screenshots

Desktop (please complete the following information):

• OS: Manjaro with GNOME 48.1

[PumpkinSeed]

Duplicated: #221