Bug 458275

Summary:	When "Kill Window" is used to kill Plasmashell, the recovery path is unclear for the user
Product:	[Plasma] kwin	Reporter:	indecisiveautomator
Component:	core	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	CONFIRMED ---
Severity:	normal	CC:	nate
Priority:	NOR	Keywords:	usability
Version First Reported In:	5.25.4
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description indecisiveautomator 2022-08-25 01:05:22 UTC

SUMMARY
The KWin "Kill Window" command (by default bound to Ctrl+Alt+Escape") can kill the Plasmashell process by clicking on an empty desktop. While this is likely intentional behaviour and I would say it should be expected behaviour, I think there are a couple of improvements that could be made:

1. Warn a user before they kill Plasmashell, maybe show a dialog and ask a user to confirm, possibly with the buttons "Ok", "Cancel" and a checkbox to not ask again. There may be a situation (which I just found myself in) where instead of clicking on the window I intended to kill, my mouse slipped and I ended up on another display, and I ended up killing the Plasmashell process. I acknowledge that this is user error, but there is no obvious way of starting Plasmashell again as far as I know, aside from the `k5start plasmashell` command. It's not a hard command but a user would need to need to know this command ahead of time, and have a command prompt open, or know how to switch to a TTY, etc etc. What I'm getting at is, for an average user there is no straightforward way of undoing the Plasmashell kill.
2. If this command is able to kill Plasmashell, maybe "Kill window" is a bit misleading. But I'm not sure what would be a better name. "Kill process" doesn't sound quite right either and is perhaps even more misleading.

I see the merit for having the ability to kill Plasmashell with the "Kill window" command but I feel like this could catch a user off-guard if they did it accidentally. It's probably not something a lot of users are going to want to do, and having a prompt to confirm to the user "hey is this really what you want to do?" could be a good safety net.

This is less of a "bug" I suppose and more of a "usability" suggestion.

STEPS TO REPRODUCE
1. Activate the "Kill window" KWin action (by default this is bound to Ctrl+Alt+Escape)
2. Click on an empty desktop
3. Plasmashell process is killed without any warning or obvious way for a regular user to bring it back

OBSERVED RESULT
Plasmashell process is killed without any warning obvious way of bringing it back. A user will be unable to access their application launcher and the desktop experience can become unfamiliar. If the user doesn't know how the command to start the Plasmashell process again, or doesn't know how to access a TTY, or has unbound or forgotten the keybind for opening up a terminal window, they may not be able to start the Plasmashell process again without a reboot.

The "Kill window" command could also have some kind of better name since it is able to kill the Plasmashell, but this is a lower priority in my opinion.

EXPECTED RESULT
Personally I think being able to kill Plasmashell with the "Kill window" command has merit, but there should be some kind of warning so only users that explicitly want to kill the Plasmashell are able to do it, and users that might do it accidentally (e.g. through a misclick) are given a warning. This provides users with a safety net while not sacrificing functionality with the "Kill window" command.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 5.19.3-zen1-1-zen (64bit)
KDE Plasma Version: 5.25.4
KDE Frameworks Version: 5.97.0
Qt Version: 5.15.5

ADDITIONAL INFORMATION
Using Wayland but this could affect X11 too

Comment 1 Nate Graham 2022-08-25 10:47:18 UTC

Perhaps KWin could automatically restart Plasma when this happens.  Generally killing plasmashell should be harmless.

Comment 2 indecisiveautomator 2022-08-25 13:37:39 UTC

There are a couple of issues I've experienced when killing Plasmashell but maybe they should be reported separately ? The most obvious is that the Digital Clock widget doesn't respect my region setting anymore and always shows 12hr instead of 24hr. This could apply to all regional settings but this is just the one I noticed last night a few hours after this bug report.

If this is a separate issue then maybe restarting Plasmashell could be a good solution. Though having a warning would mean the user would know what's going to happen. Having all their panels and such disappear and reappear (with the associated minor visual glitches of everything coming back into place) might not be the best in terms of "presentation" I guess is how I would put it.

But I'm not a dev, that's just my two cents as a Plasma user :-)

Comment 3 Nate Graham 2022-08-26 09:16:10 UTC

It sounds like your plasma settings are being lost; that definitely should not happen when you manually kill plasmashell. So please do file a bug, especially if you can reproduce it consistently.

I think auto-restarting is the right thing as when the user invoked the "kill window" functionality and clicks on Plasma, it's pretty clear what they want to do. You can say, "well, what if the user made a mistake", but this is a scary feature that luterally has a red skull and crossbones icon, which is designed to provoke alarm and make the user understand that what they're about to do is dangerous. If they use the functionality carelessly despite the existing "I'm dangerous!" visual cues, I think that's on them. :)