GTK+ is a simple and limited X11 toolkit. It can be visually attractive. But it's not something you would chose rationally based upon features, code quality, code maintainability or having a good developer ecosystem and support. Because it would come in last place on every metric, unfortunately.
There are very good reasons people don't use GTK+ for commercial projects. Or even open source projects, unless they haven't learned the hard way yet. Fundamentally: its developers don't prioritise the needs of the very application developers who should be their primary customers.
(I used to develop open source and commercial GTK+ applications. What a huge waste of time and effort that was. Utterly soul destroying how many unfixable bugs I had to find and work around.)
Do you not consider GLib and associated libraries to also fulfill this application development framework role?
GLib is a set of basic C functions for missing standard library functionality which range from acceptable to awful. An "application development framework" it is not. It's a set of simple helper functions and some primitive containers with so-so performance and very little safety.
Use the C++ standard library and avoid 99% of it with containers that work properly and classes that aren't fragile because you're still pretending that C can do object orientation and object lifetime management sanely. It can't. Constructing vtables by hand with GObject might be clever to prove a point, but it's no way to write a robust application that the compiler can actually type check and that static analysis can find problems with.
Off the top of my head there is libxml2, libxslt, librsvg, libgda, libclutter (and now GSK with GTK 4). Networking is included in the gio part of glib.
Unfortunately there are no good gtk/gobject-style libraries for generic gamepad input or chart rendering as far as I'm aware.
None of which have anything to do with GTK+ as an application development framework. They are independent projects.
The libraries you mentioned are a random collection of unrelated open-source libraries. There is no comparison. It's not "bikeshedding" to point out a completely baseless argument.
If the argument is that the Qt libraries are all developed together by paid Qt Company developers then sure, that's true, the libraries I mentioned aren't like that where one company is working on them. But that's different than saying they're designed to work together.
Ditto for "in depth documentation". ;)
I suspect the problem is lack of API stability, not the relative quality of any given pair of releases.
The only app that is close to "qualify" on this could be GIMP, but will it get over the issue of user responses like: "I only want Adobe® Photoshop®, Ableton® Live NOT this 'GIMP' or what is this thing called 'Ardour'".
- Use Auto-Night Mode to make Telegram night mode match the system Dark Mode settings.
- Also added an option to switch to system window frame in Windows and Linux.
- System notifications for Linux
Nice and seamless overall now. Get my notifications using system notifications, and looks better in Sway using system frame.