Its just an impossible problem.

Apps like to make very custom interfaces. All of CSS is great.

Platforms like consistency, so they maintain their own complex CSS.

Users like to customize everything, so CSS is powerful but will always break as its fighting the others.

More than apps liking to make custom interfaces, I think it’s more that companies like to try to make their UI into a brand, necessitating a high level of customization. If you look at the majority of FOSS software, even much of it that’s held in better regard by users (e.g. Krita), highly custom UI is considerably more unusual.

There’s not much that can be done about UI-as-branding unfortunately, but for everything else I believe that parameterization is the answer. Don’t hardcode colors, fonts, etc and instead favor framework-provided presets (like UIColor.systemBackground and UIFont.caption1 on iOS) wherever practical and that’ll for the most part make your app remain usable regardless of how the user’s themed their system, short of just using a badly made theme. This should be done anyway because it’s a huge boon to accessibility if the user can e.g. enable colorblind mode and have the reds and greens in apps adjust automatically because their devs were thoughtful enough to use Color.systemGreen and Color.systemRed instead of hardcoding #FF0000 and #008000.

libadwaita does this to a degree: https://gnome.pages.gitlab.gnome.org/libadwaita/doc/1.6/css-...

I'm working on some Gtk/desktop stuff and keep coming back to the Gtk/Gnome/Wayland bug trackers where the Gtk people are constantly stonewalling ecosystem improvements. Urgency notifications, disabling client-side decorations, themeing, etc. Stuff like "well some programs put stuff in the titlebar, therefore we can't allow a hint for the ones that don't". The Catpuccin theme is very popular and they recently threw in the towel, just for the Gtk port.

I don't know if Qt is better but I've heard about 0 drama from them... I made a poll on reddit though and for some reason people (users) still prefer Gtk to Qt.

> I don't know if Qt is better but I've heard about 0 drama from them... I made a poll on reddit though and for some reason people (users) still prefer Gtk to Qt.

I think this is probably because GTK programs tend to sport UI designs that are nicer/friendlier and less “designed by a programmer”, even if they skew overly simple. Qt leans the other direction, with apps that are generally complete from a technical standpoint but have a good deal of room for improvement in UI design.

Incidentally I think this is also why distros centered around GTK-based DEs still dominate.

I'm pretty sure the reason for Gtk being way more common than Qt has more to do with inertia (way in the past Gtk's license was more desirable and wasn't until Qt4 that changed, so any programs before or around that time that were made in Gtk remained in Gtk even after Qt4) and language availability. Specifically for the latter, C is much easier to make bindings for and GObject provides functionality for doing it automatically, thus Gtk is available in many more languages whereas Qt's use of C++ is much harder to both make bindings and do it automatically. The end result is that Gtk is simply more widely available and so much more likely to be used by someone who doesn't want to use C or C++ (the main exception seems to be Python which has official high quality bindings for C++).

The UI designs are just a byproduct, there is nothing about Qt that makes it hard/impossible to have Gtk-like designs, but since Gtk is used by a lot of programmers, when encountering a program like those you mention, the chances are higher that it is written in Gtk than in Qt because more programmers use Gtk than Qt.

(note that this is specifically about Linux desktop applications, i think overall Qt is used more than Gtk outside Linux)

I had a stint with KDE cca 6 months ago, Gnome couldn't do fractional scaling for X11 apps on Wayland, this meant my IntelliJ was unusable (this was fixed since). So I switched for a few months - Plasma was just super glitchy, panes randomly collapse into 1px width, flicker, etc. And the UI looks thrown together, apps have Windows 9x/thrown together in Visual Basic RAD vibe.

I think OP described it pretty well - stock Gnome is actually a nice desktop environment, I prefer it to Windows, does not even come close to MacOS.

TBH i haven't used KDE Plasma much. I used to like KDE 3.5, then KDE 4 was a disaster that it took several releases after KDE 5 to stabilize (i remember trying KDE Neon, supposedly KDE's very own distro that should be rock solid for KDE - and i had severe visual glitches). But the last versions of KDE 5 and KDE 6 nowadays seems fine. Again, i'm not using it much, i mainly use Window Maker (X11) and use KDE Plasma only on my laptop as well as on my desktop when i want to try something in a more "windows-like" environment or as a different user (for default configurations, etc).

I can believe that KDE Plasma still has issues though, it seems some sort of bomb was thrown during KDE 4 times in the codebase and it still has to recover. Though if nothing else, i do use KDE apps outside of Plasma (Kate, Krita, Dolphin, Okular, Spectacle) and they all seem very solid.

I think Gtk+Gnome and Qt+Kde are being mixed here and it's creating some confusion.

After a parent said that Gnome looked better than Kde I looked it up and found a number of posts criticizing Kde design decisions (padding, etc). I fully believe the Gnome people have a better design decision. But I don't think that criticism applies to Qt itself, necessarily.

It’s not a perfect rule but I find that Qt apps tend to resemble KDE apps and have questionable design choices more often than not, even those that aren’t related to the KDE project in any way.

It’s consistent enough that it makes me wonder if maybe something about the tooling is partially to blame.

GTK theming was a mess long before libadwaita came along.

It's no secret that the GNOME/GTK guys _hate_ theming. So much so, that made an entire website for it: https://stopthemingmy.app/

The theming they dislike isn't the theming their users are doing. Their biggest issue is distros packaging their own theme, which can easily break an entire suit of applications without the user knowing it's because their distro decided to override the colours or mess with widths. As the page you linked says:

> If you like to tinker with your own system, that’s fine with us. However, if you change things like stylesheets and icons, you should be aware that you’re in unsupported territory. Any issues you encounter should be reported to the theme developer, not the app developer.

Theming Gnome by editing the default style sheet is akin to distro theming the web by modifying Firefoz's default style sheet. Tons of websites will break in weird and interesting ways but the user won't know to blame the distro, because they never touched user.css or even know it's possible to change the default.

The same breakage also happens on KDE and Qt applications (and more, I have seen Eclipse launch with black text on a black background when dark mode is enabled) but the developers don't seem to care as much, or are less bothered by the false bug reports. I've also experienced the "this doesn't look anything like the screenshots" feeling because of the theme I have applied, but at least I know it's my own fault.

To be fair, this one is specially to address the issue of a distro theming an app, breaking it, and that leading to a bug report at the upstream even though it's the distro at fault.

If a user is willing to take responsibility for breakage and such, then I'm not sure the devs are against theming as such.

> If you like to tinker with your own system, that’s fine with us. However, if you change things like stylesheets and icons, you should be aware that you’re in unsupported territory. Any issues you encounter should be reported to the theme developer, not the app developer.