>For example, I don't want GTK-3, I only have GTK-2 installed. It could be all fine and dandy if, one after another, year after year, applications wouldn't give

>For example, I don't want GTK-3, I only have GTK-2 installed. It could be all fine and dandy if, one after another, year after year, applications wouldn't give up their GTK-2 backend to only maintain/develop their GTK-3 one. gtk2 is deprecated, so it makes sense that any actively-supported applications are moving to gtk3, which is still supported. By refusing to use gtk3, you're locking yourself out of not only newer applications that were only written for it, but older ones that have moved to it. Why do you think an actively-maintained application should stick with a deprecated toolkit? >On Qt side, there are applications which requires an exact version of Qt (not only the main version Qt-3/4/5, but the point version), or require KDE, or require an exact version of KDE. In all my years, I've never seen this with an actively-maintained application. Of course, I generally stick with stuff that's available in my distro repo, so I never have any trouble. Also note that with both gtk3 and Qt5, both these toolkits have been around for something like a decade now. Looking at Wikipedia, gtk3 3.0 came out exactly 9 years ago (10-02-2011), and Qt5 came out on 19-12-2012. Neither of these is at all new. I will grant you, though, that gtk3 is now already headed the way of the dodo, since they've announced gtk4. Personally, I'm not a fan of gtk and prefer Qt as it seems much more stable and better for GUI development anyway, and I don't see anything about Qt5 being phased out. Qt is also used a lot in embedded systems in industry, unlike gtk. >the visible changes were: icons are now flat and monochrome (i.e. you cannot recognise one from another) That's all the rage these days. I'm not a big fan either, but it's what most users want. This isn't a brand-new fad either; it's been going on for years now. I do wish I could try living in the alternate universe where UI design mostly stuck with way things were done in the mid-2000s.