windows dock at invisible line in xfwm4

[Luca Steinke]

I did a video (sorry, music in the background):

https://www.youtube.com/watch?v=OBN6WLskQ-U

from the #xfce channel on freenode:

<killermoehre> phre4k: ok, now I want »xwininfo -size -name plank« from both the hidden and the unhidden window
<phre4k> killermoehre: both the same: http://pastebin.ca/3248299
<killermoehre> phre4k: well, that's bad. if plank is only hiding visualy, but is not resizing its window, how should xfwm4 know that it shouldn't dock there?

further info:

Plank 0.10.1
xfwm 4.12.3

Arch Linux, Kernel 4.2.5-1-ARCH

X.Org X Server 1.17.4

Radeon R9 280X Tri-X
driver: radeon 2.43.0

DE: xfce4 4.12.3
installed plank with pacaur -S plank.

[Rico Tzschichholz (ricotz)]

If the dock is meant to hide in anyway there is no reason to support "snapping".

Plank sets "struts" only if it is not hiding at all. Those would be evaluated by your window-manager to support what you want.

[Luca Steinke (phre4k)]

>If the dock is meant to hide in anyway there is no reason to support "snapping".

Yes, exactly. Look at the video, it snaps at an invisible border.

[Rico Tzschichholz (ricotz)]

I see, still it is a problem of xfwm4 which shouldn't handle dock-type windows that way.

[dd23 (dd23)]

I have a very similar problem with plank, however, I can actually see the line where the windows dock, which is very annoying.

The line disappears when I quit plank.

This happens on all screens, on all orientations and independent of auto-hide - short: always.

My setup:
Manjaro Linux 16.06.1
xfce 4.12
plank 0.11.2

Is this an also an issue with xfwm, or does that come from the more recent plank version?

[dd23 (dd23)]

The shadow can be deactivated by setting xfwm4 /general/shadow_dock_shadow to false for example using xconf-editor.

So this issue seems to be a xfwm problem, after all.