In reply to Font editor (FontLab?) feature suggestion: floating sidebearings linked to outlines in glyph:
"If one is moving the x extrema of o, e.g. and the right side bearing is sliding along with it, no big deal — that's basically class spacing."
Well, class spacing would be an additional wrinkle on top of that (which I would like to see, actually)
"The other way, though, one moves the right side bearing, and what one would like to happen is complicated."
Maybe you and I have different ideas of what we would like to happen? For me, even if "sidebearings linked to extrema" is on, I'm assuming that's a one-way link and if I deliberately move the sidebearing, that's because I want to change it. So I don't want any change in the current behaviors if I grab the sidebearing and move it: it moves, end of story.
Now, the interactions with class-based sidebearings are interesting, admittedly. Probably if it's the base glyph for the class, the change affects all class members. If it's not the base glyph in the class, then the current glyph becomes an exception in the class?
Cheers,
T