Broken maximisation toggle

[dsalt]

Toggling the Steam main window size using Steam's own toggle-size button. (It doesn't matter which window; this one is merely most convenient.)

Environment is Devuan daedalus, Xfwm4.

Initial state:

$ xwininfo -id 0x6c00039 | grep -e Width -e Height -e Absolute
  Absolute upper-left X:  2280
  Absolute upper-left Y:  136
  Width: 1024
  Height: 768

First time (normal maximisation):

$ xwininfo -id 0x6c00039 | grep -e Width -e Height -e Absolute
  Absolute upper-left X:  1920
  Absolute upper-left Y:  0
  Width: 1920
  Height: 1080

Second time (restore):

$ xwininfo -id 0x6c00039 | grep -e Width -e Height -e Absolute
  Absolute upper-left X:  1920
  Absolute upper-left Y:  0
  Width: 1920
  Height: 1080

Only obvious difference is that there's now a slightly thicker border and the resize handle is visible, as if the window size were properly restored.

There is a brief flicker which is not present if the window size is toggled further (unless the window is actually resized at some point, at which point we're essentially back to the initial state). Also, the border thickness and resize handle are toggled as expected.

The expected result of the restore step is that the window is at its original position and size.

No log text was generated while testing this.

(This bug has been present for several months at least.)

[dsalt]

Checked with another WM (sawfish). No difference.