I am using a tiling window manager (Awesome) on Linux (Arch). Keepnote does not play nicely with it. Its window is always on the floating layer, does not tile, and I cannot move or resize it (it always fills the screen). Is it a transient window?

That's strange. I use gtk.Window(type=gtk.WINDOW_TOPLEVEL)

I don't think it is a transient window.

I discovered that I'm able to resize the window using the little symbol on the lower right of the window. But that is it. Still no moving or resizing.

I'll see if I can try it on another similar WM.