Window does not appear in GNOME's activities overview

[Paul Nickerson]

When I have a Terminator window somewhere on my screen, and then I move my mouse to the top left of the screen to activate the Activities Overview screen, the Terminator window does not show up. All other windows of all other kinds of applications do show up; Terminator is the only one missing.

I am running Fedora 26 (Workstation Edition), and on log in I select "GNOME on Xorg" (Wayland does not have a hardware accelerated mouse cursor). My GNOME version is 3.24.2, and X.Org X Server is 1.19.3. Terminator is 1.91, from the Fedora repository (terminator-1.91-2.fc26.noarch). I also tried the cloning the repository and running that Terminator, as instructed in the bug report guidelines.

Also of note: I use the Window List GNOME extension (display a window list at the bottom of the screen). All other windows get listed at the bottom of the screen, but no Terminator windows get down there.

I think this started yesterday. I looked through my dnf install log, and it doesn't look like any GNOME, Xorg, or Terminator related packages got updated recently.

I tried "GNOME" and "GNOME Classic" on login, and those both have working Terminal windows.

[Stephen Boddy (stephen-j-boddy)]

OK, So on my Ubuntu 16.04 LTS, with Gnome Shell 3.18 it all works fine, including with the window list extension. So I have to assume that Gnome have started doing or expecting something new from the application. Couple of things occur to me:
1) Gnome has decided to start ignoring applications that haven't changed to follow the proscribed path of divinity (i.e. Must create a GtkApplication, yadda yadda yadda!)
2) There is some difference between a Terminator window and a non-Terminator window as presented to the X Window system, and gnome-shell is ignoring Terminator because it doesn't like something to do with the Terminator window. (You could try xprop on the Terminator window and a working non-Terminator window, and attach both outputs here for comparison. It might provide a clue...)
3) Do Qt/KDE applications show up properly too? Nothing else is invisible at all? Because that's very strange.

[Paul Nickerson (pgn674)]

Thank you for looking into this.

I tried xprop on Terminator (from Fedora repo), nautilus, qtdemo-qt4, glxgears, xeyes, and kompare. I also saw that there's an experimental gtk3 series of Terminator, so I got that (bzr branch lp:terminator/gtk3), ran it, and used xprop on that too. Terminator always had the no-appearance problem, including the gtk3 version, and no other windows had the problem, including the QT4 and KDE ones. I've also run Geany and SpeedCrunch, and some things not in the Fedora repos including HipChat and Yubico Authenticator. Terminator is still the only one with the problem.

xprop outputs are attached.

[Stephen Boddy (stephen-j-boddy)]

Can't believe this didn't occur to me earlier, but by a circuitous route I can see:
_NET_WM_STATE(ATOM) = _NET_WM_STATE_SKIP_TASKBAR, _NET_WM_STATE_FOCUSED
for the Terminator window. Note the "SKIP_TASKBAR" bit.

Pretty sure you have enabled the "Hide from taskbar" option in the Preferences. Deactivate and your windows will reappear. (Before you ask, yes some people do like to hide the console from the task bar :-)

[Paul Nickerson (pgn674)]

Ha, that was it. Terminator Preferences > Global > Behavior > Hide from taskbar was checked. I have no idea how that got enabled; I don't think I even opened up the preferences window any time recently.

Oh well, disabling that option did indeed make everything work as expected. Terminator now shows up in the activities overview, and in the window list extension. I also notice now that the menu in the panel at the top of the screen had been missing, and the Terminator icon in the activities overview launcher did not get a blue underbar indication Terminator was open, nor did its right click menu list out the open Terminator windows. That _NET_WM_STATE_SKIP_TASKBAR option is really taken seriously by GNOME.

I guess this is an actual case where "that's not a bug, that's a feature!" really does apply. Thank you again for your help. I am all set.