on all thinkable distributions
No, just Ubuntu, Mint, Arch probably. The point is that the change is relying on icon themes, and distros are the thing that provides them, and possibly differing sets on each desktop, as far as we can tell all but Debian Adwaita provide sensible `gtk-clear` icons (since nobody has complained), but do they provide sensible `edit-clear-symbolic` icons?
Without checking we just don't know.
postpone this after 2.0.
Agreed, until we are confident we won't break a whole lot of other systems to fix one.
too close to the midnight
Go to bed while I have breakfast :-)