No window buttons

Submitted by Mikhail T.

Assigned to Simon Steinbeiß @ochosi

Link to original bug (#16019)

Description

After the recent upgrades -- to 4.14.1 -- on three different computers (running FreeBSD of different versions), there are no longer any buttons shown in the "window buttons" applet.

Not for the open applications, not for the minimized ones. None. Indeed, a minimized app can only be restored by cycling through Alt-Tab -- and, sadly, some of them (like Citrix' wfica) do not appear on that list at all.

The separate "windows menu" applet seems to work properly, but the "windows buttons" is not showing anything.

I'm surprised, this hasn't been reported yet -- maybe, something is specific about my environment... For example, I have LANG set to Ukrainian (uk_UA.KOI8-U)...

Version: 4.14.1

added 5. Window Buttons / Tasklist label

Mikhail T. said:

Just discovered, that my ~/.xsession-errors is full of messages like this:

(xfce4-panel:19957): libtasklist-CRITICAL **: 23:03:30.194: tasklist-widget.c:1155 (xfce_tasklist_size_allocate): expression 'area.height == tasklist->size' failed.

Why would this be?

Mikhail T. submitted a patch:

First, I added a debugging printf to tasklist-widget.c, and found, that the area.height is 30, but tasklist->size is 48...

I then modified the code as attached, and got my buttons working again. Please, review and commit soonest. Thank you!

Patch 9105, "Relax check of area-size":
p

Simon Steinbeiß @ochosi said:

Could you either attach your panel config (feel free to export it with xfce4-panel-profiles) or describe the setup in a way so that I can reproduce the bug? Thanks (also for debugging and attaching a patch)!

Mikhail T. said:

There is nothing special about the panel -- it is horizontal, at the bottom of the 2nd of two screens. To the left is the application menu, followed by the application buttons. Then -- the workspace-switcher (four workspaces), then:

. weather . snapshot . keyboard-switcher . clock

The panel seemed narrow after the upgrade, so I widened it up a little -- which means, the current settings aren't what I struggled with.

May it be, that area.height could some times be less than tasklist->size?

xfc..@..am.org said:

I'd like to confirm this bug: no window buttons. Problem remained after upgrading to 4.14. Oddly, this bug hit only one of four xfce users on this machine. After reading Mikhail's notes, we tried changing the Panel/Display/Measurements/Row size (pixels) slider, and the window buttons reappeared. They don't seem to disappear again even at the original setting of 48px.

xfc..@..am.org uploaded an attachment:

This is the config after the "size slider" fix. Not sure if it is helpful. Windows menu was added as a work around for broken window buttons while debugging.

Attachment 9168, "xfce4 panel config":
xfce4-panel.xml

xfc..@..am.org said:

Oh, and we also saw the .xsession-errors:

(xfce4-panel:12780): libtasklist-CRITICAL **: 22:00:46.579: tasklist-widget.c:1155 (xfce_tasklist_size_allocate): expression 'area.height == tasklist->size' failed.

Simon Steinbeiß @ochosi said:

@Mikhail: So while I can see why the patch would fix your problem, I'm wondering why or how you're getting that problem in the first place. Are you using a theme that is modifying the tasklist somehow? Or do you have any other instructions on how to reproduce? (I'm open to pushing the patch to fix your issue, but I'd prefer to understand the root cause of this first.)

Mikhail T. said:

Sorry, I can't recall the exact series of events :( Could I have resized the entire bar down a little while using an earlier version of xfce4?

No, I'm not using any fancy theme...

Christof P. said:

@Simon

I think i can provide you with some more info as i experienced the same problem too.

I got this problem while upgrading from xfce 4.12 on RHEL(installed from the EPEL repo) to xfce 4.14 on RHEL(compiled from source).

While upgrading to the new version(on a new machine, so not really upgrading), i use the (default.xml) panel config of the previous version.

After searching for about 2 days what caused this issue, i discovered that i also got the messages below when i launched the 3 commands below from within xfce """ pkill xfce4-panel setenv GTK_DEBUG "interactive xfce4-panel" xfce4-panel """ (xfce4-panel:8390): libtasklist-CRITICAL **: 12:41:02.988: tasklist-widget.c:1155 (xfce_tasklist_size_allocate): expression 'area.height == tasklist->size' failed.

As it seemed to have something to do with the size of the panel, i tried changing the "Row size(pixels) settings" from within xfce (right click on panel on top -> panel preferences -> go to panel 0(my top panel) -> change the "Row size(pixels) settings" slider which was on 48 by default), and suddenly the "window buttons" from the applications appeared.

After doing a diff between the original default.xml and the new default.xml(after moving the slider), i noticed that xfce added the 3 lines below on the bottom of the section for panel 0:

So this issue is reproducable by removing those lines again.

So i think the solution would be that when you start xfce 4.14 from the first time, it should add those 3 lines to the default.xml

If you need more info, please let me know.

greetings, Christof.

Is it permanent for you people, or only sometimes appearing but sometimes disappearing? I have a kind of similar problem with my xfce4-panel 4.14.4 (on ArchLinux), but for me, the Window Buttons only disappear in some situations, but not always. I still haven't figured out the rule by which the buttons appear and disappear.

One way to guarantee them re-appearing is to hover the mouse on the left side of where Window Buttons should be. This is meant as a symptom of a problem, not work-around of course.;-)

UPD: The better way to describe the problem I'm having is this bug: #188 (closed)

unassigned @ochosi

added Patch label

So in fact, according to #267 (comment 8208), it would be a problem of backward compatibility between 4.14 and 4.12, which is quite easy to fix. I think we can close.

closed