But I do take issue with attacking developers who write applications for free, and contribute to the Linux ecosystem, for making a reasonable request to platform developers.
I understand that the devs do not want to be responsible for bugs stemming from broken themes, but this is the wrong solution. Ultimately the solution is a better theme API, not this which would essentially stop custom themes all together for most end users.
In other comments people argue that this isn't aimed at end users, but end users would of course also be impacted from this.
I don't see a good technical solution here, but I see two social ones: a) developers of FLOSS must understand they're writing software that can and will be modified and re-released by others, sometimes individuals and sometimes organized groups (like people making Linux distributions); and b) users need to understand that if they have a problem with their software, they should reach out to people from whom they got that software for support. If you got a program from developer's home page, you should contact them directly. If you got it from your distro, then distro maintainers should be your first line of support.
(Also c), some users won't understand b), and forwarding support requests to appropriate people is just part of publishing FLOSS.)
How is releasing software under a license and asking people not do things allowed by that license reasonable?
If GTK3 still does not support theming, that explains why theming causes issues. In which case it would be better to implement proper theming support because stopping distributions from theming clearly doesn't work.
Oh yes, people have always done it, via one hack or another, and as long as it was more of a "for people who really want to fiddle" it wasn't that much of an issue.
But now expectations have risen, people expect more solid behaviour and look/feel from their apps, and distros routinely have quite different GTK themes.
