Comment 16 for bug 1958670

I gave those changes a go, with both xdg-desktop-portal-gtk and xdg-desktop-portal-kde, the behaviour in both works as expected; the filename is automatically appended and saves without an extension work just fine.

In the case of the KDE backend, the file dialog will actually assist with swapping and appending the file extension automatically, so KDE users should rarely save extensionless files (there's an option on the UI to manage it). From Pinta's perspective, the user just always happens to save a file with an extension (which makes me wonder why GTK doesn't do the same thing, given how severe the consequences can be).

Of course, there's still the behaviour of revealing the /run folder in bug 1958667, but as far as data loss is concerned, this looks a lot better. ( I won't say it's perfect because I'd rather give more than 5 minutes of casual testing given this has bitten once before ! )