This week in KDE: Explicit Sync

Saturday, 13 April 2024 | Nate Graham

This week something big got merged: support for Explicit Sync on Wayland!

What does this do? In a nutshell it allows apps to tell the compositor when to display frames on the screen, reducing latency and graphical glitches. The effect should be particularly noticeable with NVIDIA GPUs, which only support this rendering style, and not having support for it on Wayland was the most common source of random graphical glitches and slowdowns.

This work was done by Xaver Hugl, and lands in Plasma 6.1. You can read more about it in a recent blog post he wrote on the topic!

In addition to that impactful but technical change, this was a week of many UI improvements and bug fixes as well:

UI Improvements

Improved the visual quality of cross-screen screenshots that Spectacle takes when using multi-screen setups where the screens have different scale factors (Noah Davis, Spectacle 24.05. Link)

Improved quality of blurs, pixelations, and shadows in Spectacle’s annotations (Noah Davis, Spectacle 24.05. Link)

KWrite now shows a hamburger menu by default instead of a traditional menu bar, and the hamburger menu has gained an assortment of curated actions on the top to speed up access to them (Nathan Garside and Christoph Cullmann, KWrite 24.05. Link 1, link 2, and link 3):

Just KWrite! Nothing has changed for Kate.

Filelight now throws fewer annoying modal dialog windows in your face: it now shows directory access errors using inline placeholder messages, and failures to add duplicate exclusion paths using small toasts/passive notifications (Han Young, Filelight 24.05. Link 1 and link 2)

In the “Get New [Thing]” dialogs, the warning shown at the top is now different and more warningy if the available content has the potential to run executable code on your system (David Edmundson and me: Nate Graham, Plasma 6.1 and Gear apps 24.05. Link 1 and link 2):

In Plasma’s traditional Task Manager widget, the threshold for showing any text is now smaller, so you’ll see text more often even at relatively narrow task widths. This is based on the idea that if you’re using this widget, it’s because you want to see text! (me: Nate Graham, Plasma 6.0.4. Link)

On Wayland, the Dialog Parent effect that dims parent windows when dialogs are active now temporarily disables the dimming when the dialog window is a color picker that’s currently picking a screen color (Ivan Tkachenko, Plasma 6.1. Link)

System Settings’ Virtual Desktops page has now adopted the common “controls on the header row” paradigm to increase the space available for content (Jakob Petsovits, Plasma 6.1. Link):

In Plasma’s Power and Battery widget, the controls and UI for blocking sleep and screen locking have moved from the header into the view, matching the location of other interactive controls and preventing the header from becoming super chunky when multiple apps are inhibiting sleep and screen locking (Natalie Clarius, Plasma 6.1. Link):

System Monitor now shows a tooltip with the full text when you hover over an elided piece of text in one of the table views (Joshua Goins, Plasma 6.1. Link)

Made the header message on System Settings’ File Search page frameless and border-touching, making use of new API created to enable this purpose. This API was also used for the message in the “Get new [thing]” dialog shown earlier. So expect to see more of this kind of thing in the coming weeks! (me: Nate Graham, Plasma 6.1. Link 1 and link 2):

Folder popups invoked from a Plasma panel can now be resized if you’d like more space to see everything in them (Ivan Tkachenko, Plasma 6.1. Link)

If you preferred the old style of app launching in Plasma’s traditional Task Manager widget whereby an app’s pinned launcher would disappear when launched, you can now get that back (Niccolò Venerandi, Plasma 6.1. Link)

Middle-clicking a desktop in KWin’s Overview effect no longer instantly removes it, because this made it too easy to accidentally destroy your layout (me: Nate Graham, Plasma 6.1. Link)

The radius of rounded corners throughout Breeze-themed UI elements has now been standardized at 5px, much better than the previous random assortment of corner radii that ranged generally from 2-5px, with some being as high as 8 or 16px! This is an easily bikeshedded topic, so please try to restrain yourselves; check out all the other screenshots in this post, which feature the change—I bet you thought they looked pretty good before I explicitly mentioned that the corner radius had increased, right!? 😁 (Akseli Lahtinen, Plasma 6.1 and Frameworks 6.2. Link)

Bug Fixes

In Dolphin’s Details view, navigating to a subdirectory no longer resets the current sort mode (Felix Ernst, Dolphin 24.02.2. Link)

Gwenview no longer inappropriately blocks sleep and screen locking when simply viewing an image (Daniel Strnad, Gwenview 24.02.2. Link)

Fixed a nasty bug in Spectacle that could cause the rectangular region overlay to get stuck on screen when taking a rectangular region screenshot right after a screen recording without quitting and re-launching Spectacle first (Noah Davis, Spectacle 24.05. Link)

Plasma’s Night Light feature no longer unintentionally connects to Mozilla Location Services to geolocate you for the purpose of figuring out the Night Light transition time when you don’t have that setting turned on (Natalie Clarius, Plasma 5.27.12. Link)

Plasma no longer crashes when you close the notification that gives you an opportunity to undo removing an Icon widget (Nicolas Fella, Plasma 6.0.4. Link)

Modal font dialogs in Plasma 6 are now ugly, but at least they work again; our previous styling approach caused them to end up non-interactive and has been reverted for now pending a better solution (Nicolas Fella, Plasma 6.0.4. Link)

Discover once again shows you everything you have installed on its “Installed” page—not just an assortment of packages that depended on what distro you were using (Harald Sitter, Plasma 6.0.4. Link)

When scrolling down in one app category on Kickoff and then switching categories, random items from the former category no longer sometimes appear inappropriately on the new page (David Redondo, Plasma 6.0.4. Link)

On Wayland, the color picker dialog no longer returns incorrect colors when an ICC profile is applied to the display (Xaver Hugl, Plasma 6.0.4. Link)

Fixed a strange issue whereby items in Plasma’s list view mode Folder View popups on a panel could only be highlighted when moving the cursor downwards, rather than upwards (Akseli Lahtinen, Plasma 6.0.4. Link)

Fixed a bug that made it possible, under certain circumstances, to drag a window completely off the screen (Yifan Zhu, Plasma 6.0.4. Link)

On Wayland, the clipboard menu that appears when you hit Meta+V no longer goes underneath windows set to always be on top (Tino Lorenz, Plasma 6.0.4. Link)

In KWin’s Overview effect, the thumbnails for inactive virtual desktops are now live, not static (David Redondo, Plasma 6.0.4. Link)

Fixed a problem creating new Wireguard VPNs (Stephen Robinson, Plasma 6.1. Link)

Keyboards are no longer sometimes shown as mice on System Settings’ Mouse page (me: Nate Graham, Plasma 6.1. Link)

Rapidly toggling the “Floating” setting for a Plasma panel on and off no longer sometimes causes the panel to get stuck in a position where it’s not floating, but also detached from the screen edge (Vlad Zahorodnii, Plasma 6.1. Link)

Discover no longer mislabels apps that get removed from a Flatpak repo as being not installed when they are in fact still installed (Aleix Pol and Ivan Tkachenko, Plasma 6.1. Link)

Fixed a case where KDE apps could run out of memory when told to open certain types of malformed image files (Mirco Miranda, Frameworks 6.1. Link)

Fixed the most common crash in the Baloo file indexing service, with 113 duplicates as of the time of writing (Christoph Cullmann, Frameworks 6.2. Link)

Fixed a rare case where KIO could exhaust all memory while trying and failing to process HTTP requests under certain unusual circumstances (Harald Sitter, Frameworks 6.2. Link)

WebDAV files accessed through Dolphin or other KDE apps once again show the correct modification times (Fabian Vogt, Frameworks 6.2. Link)

Other bug information of note:

Performance & Technical

After Qt changes regressed this, changing color schemes is once again nearly instant, giving the “blend changes” KWin effect enough time to provide a smooth transition between the colors (Kai Uwe Broulik, Frameworks 6.2 Link)

Files and folders on the desktop that are copied or dragged are now made available via the Portals system, so dropping them into sandboxed apps now works as expected (Karol Kosek, Plasma 6.0.4. Link)

…And Everything Else

This blog only covers the tip of the iceberg! If you’re hungry for more, check out https://planet.kde.org, where you can find more news from other KDE contributors.

How You Can Help

KDE has become important in the world, and your time and labor have helped to bring it there! But as we grow, it’s going to be equally important that this stream of labor be made sustainable, which primarily means paying for it. Right now the vast majority of KDE runs on labor not paid for by KDE e.V. (the nonprofit foundation behind KDE, which I am a board member for), and that’s a problem. We’ve taken steps to change this with paid technical contractors—but those steps are small due to limited financial resources. If you’d like to help change that, consider donating today!

Otherwise, visit https://community.kde.org/Get_Involved to discover other ways to be part of a project that really matters. Each contributor makes a huge difference in KDE; you are not a number or a cog in a machine! You don’t have to already be a programmer, either. I wasn’t when I got started. Try it, you’ll like it! We don’t bite!