I’m a heavy user of Firefox profiles. Apart from using different profiles for different activities, I also have a few extra profiles that all run in the Default activity.

This means that I need to have different icons shown in Plasma’s panel in order to be able to easily differentiate which profile a window belongs to.

Sure, I use the tasks applet which shows the window title instead of the icon-only one (I prefer usability to minimalism), but still, it isn’t enough as sometimes the active tab in a Firefox window might not have the most informative title.

Plasma seems to rely on the application name and the window class when choosing the icon it will show in the panel. Which means that, by default, all Firefox instances end up having the same icon.

Fortunately, Firefox allows you to specify the window class it should use through command line arguments.

firefox -P ProfileName --class WindowClassName

And, to connect a launcher to a specific window class, you just need to add the following line to the .desktop file:

StartupWMClass=WindowClassName

So, in order to have a nicely supported Firefox profile, you can create a launcher with a desktop file similar to the following:

[Desktop entry]
Exec=firefox -P SocialSites --class FirefoxSocialSites
Icon=user-available-symbolic
StartupWMClass=FirefoxSocialSites

It also works with Firefox derivatives such as Librewolf (which can be seen in the screenshot above) and others.

Wayland

For Wayland users, a comment by John Kizer might be useful:

On Wayland, I’ve ended up just using KWin Window Rules (based on a substring of the window title, and setting the desktop file name) in combination with .desktop files that launch Firefox to the site in question and have the desired icon associated.

EDIT: And another approach for Wayland by Christoph Martin:

There’s no need for messing around with window rules - at least not for Firefox.

If you use the –main flag instead of the –class flag for the Firefox invocation in your .desktop file, you should get the desired effect - at least in the Icons-Only Task Manager. Note that StartupWMClass still needs to match the value of the –main flag.

The above works on my machine, that is under Plasma 6.0.5 on the Fedora 40 KDE spin.

Credit: https://superuser.com/a/1784867

I was keeping myself on Plasma 5.x until recently. I got so accustomed to the Bismuth window tiling script for KWin that I couldn’t imagine myself updating to Plasma 6.x where Bismuth doesn’t work.

Unfortunately (?), one of the recent Debian updates broke Bismuth in Plasma 5.x as well, so I had nothing keeping me on the old version anymore. I’m now (again) running the development version of (most) KDE software.

Since the update, I managed to make the Qtile tiling window manager work with Plasma to some extent. But the integration between Qtile and Plasma I hacked was less than ideal, and I kept switching between KWin which worked perfectly, as KWin does, but without tiling, and my Frankenstein Qtile which didn’t work that well, but it had tiling.

Maybe I’ll write about it if I get back to hacking Qtile, but that might not happen any time soon because…

Krohnkite

Then I saw the news that the predecessor of Bismuth – the Krohnkite script has been ported to KWin 6 – see the announcement on reddit, github to get and review the code, and kde store for the package you can install.

Huge kudos to all who are involved in the rebirth, the script works as well as it did with KWin 5.

Window decoration

The only thing missing was the simple ‘just a line around the window’ window decoration that Bismuth had.

Now we have that as well, I’ve ported the original Bismuth window decoration to KWin 6 (nothing huge, just a few tiny changes to make it compile). The code, and the installation instructions are available on github.

Some time ago, Marco started a series of articles on SObjectizer. It is starting to become the source for all things SObjectizer – it is currently at post number 19 – quite an endeavour.

For those who haven’t met SObjectizer before, it is a framework for writing concurrent applications which supports the actor model, publish-subscribe…

EDIT: The series are available on Marco’s blog as well as on dev.to

People who have visited any of the larger C++ conferences surely know Rainer Grimm, know his talks, workshops and books.

Unfortunately, he has been diagnosed with ALS, a serious progressive nerve condition.

Since ALS research doesn’t get much attention or funding, Rainer started a fund raising campaign for funding ALS research with ALS-Ambulanz of the Charité and I Am ALS organization.

The recording of my keynote at this year’s Meeting C++ in Berlin has been published on Meeting C++ channel on YouTube:

The talk is about prog (or progressive) C++ and idioms that make C++ code provably safe.

The slides are available in the Traning and talks section.

Huge thanks to Jens for tirelessly organizing Meeting C++ for this many years (this was my tenth year presenting at Meeting C++, and I skipped a few).