Bug 374571

Summary:	Created starter runs wrong command
Product:	[Plasma] plasmashell	Reporter:	Lukas Ba. <kdeu>
Component:	Icons-only Task Manager	Assignee:	Eike Hein <hein>
Status:	RESOLVED NOT A BUG
Severity:	normal	CC:	plasma-bugs-null
Priority:	NOR
Version First Reported In:	5.8.5
Target Milestone:	1.0
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Lukas Ba. 2017-01-05 01:11:32 UTC

* Created starter runs wrong command
* no way to create correct starter
* wrong icon

I have created a custom .desktop file for starting Firefox.

> ~/local/share/applications/sandbox-firefox.desktop

> [Desktop Entry]
> Type=Application
> Name=Sandboxed Firefox
> GenericName=Secured Firefox
> Exec=firejail /usr/lib/firefox/firefox
> Categories=Network
> Icon=firefox-symbolic
> Terminal=false

When i start firefox directly from this .desktop file (via krunner), the correct command "firejail /usr/lib/firefox/firefox", as per the Exec= line is executed.

However, its icon is not the "firefox-symbolic" icon i have defined in the sandbox-firefox.desktop file, but the standard-firefox-icon.

Then i right-click on the standard-firefox-icon shown in the Icons-only Task Manager to create a new starter.

When i click on this starter, the wrong command is executed.

This command is "firefox", and probably taken from the standard .desktop file from /usr/share/applications, which says Exec=firefox %u.

AFAIK, there is no other way of adding a starter to the Icons-only Task Manager than right-clicking on a running application, which means i can't add a starter in this Task Manager that starts sandbox-firefox.desktop.

Comment 1 Eike Hein 2017-01-05 05:26:03 UTC

Rename the .desktop file to match the WM_CLASS of your Firefox window, or find a way to change its WM_CLASS to "sandbox-firefox", otherwise the Task Manager can't match the two up.

Comment 2 Lukas Ba. 2017-01-05 15:21:21 UTC

(In reply to Eike Hein from comment #1)
> Rename the .desktop file to match the WM_CLASS of your Firefox window, or
> find a way to change its WM_CLASS to "sandbox-firefox", otherwise the Task
> Manager can't match the two up.

Changing the WM_CLASS to "sandbox-firefox" with xprop -s doesn't achieve anything.

The task manager doesn't react to changed WM_CLASS.

Comment 3 Eike Hein 2017-01-06 05:54:41 UTC

It works fine for me, but note that you can't use xprop. xprop -s uses XChangeProperty, which can't set the WM_CLASS property because it doesn't support the stupid special format history cooked up for WM_CLASS (two consecutive null-terminated strings in a string prop for the two parts that make it up). I recommend using xdotool, which uses XClassHint and can set the required struct format. E.g. I turned my Firefox into Konversation with:

xdotool set_window --class konversation 0x4e00010
xdotool set_window --classname konversation 0x4e00010

When you then use the context menu to add a launcher, and make sure Firefox is later using this WM_CLASS again, things fall into place.