On Wed, Apr 22, 2020 at 10:20 AM Eli Zaretskii <
address@hidden> wrote:
> The window looks are different between platforms anyway.
No, not really. They are extremely similar, actually, modulo a few
unimportant bells and whistles. At least the parts that are relevant
to Emacs are almost identical.
I would agree with this "not really" sentiment, but extend it to include the differences between icon themes, and where such things work at the OS level, between OS's. The point of icon themes is to make them all fit together, and the point of standardized system icons is to have them all fit together, and the users have shown (for many, many years now) that they understand this, and can handle the shifts with aplomb. Yes, it is possible for someone to install a wacky gui-customization pack that changes the left-arrow into a sausage and the file-folder into a rainbow, but the only people who do such things are askign for exactly that behavior, and aren't going to be upset that emacs' toolbar changes along with everything else.
As a practical matter, emacs will need a set of reasonable fallback defaults, for systems that don't have system-wide settings; we can continue to use those when the gui environment doesn't help us. The result will certainly look no worse than the current mixture of icons one can find in the emacs toolbar. It's very likely that we can improve that set of fallbacks by adopting a single source for them, such as the GTK or KDE options mentioned earlier.
A techincal wrinkle here is how those icons are displayed and how they're stored inside emacs. By way of example, the two KDE icon sets that were suggested (Breeze and Oxygen) use different file formats: one uses PNG images; the other SVG. (Oddly, the SVG images are distributed in several different sizes, which would seem to belie the advantage of using scalable images in the first place.) Scalable icons like SVG would be nice for the current era of high- and low-density displays, but my understanding is that SVG is the least well supported image format inside emacs across our various platforms these days.
~Chad