Feature suggestion: changing metrics of brace layers

could changing the values of a glyph in the lower left palette when in the ‘Font’ window also change the values of that glyphs brace layers?

That is normally not what you want. The brace layer usually has a different spacing. You can use metrics keys and they will be correctly applied to the brace layers.

Or do you mean bracket layers.

yes, I mean bracket layers. sorry.

Bracket layer might need the same side bearings. But again, not always. I try to find a way to set it to sync.

Is there any update or workaround for that?

My bracket layers (a, e) normally just have thinner bars in the middle, the spacing can be the same as in the normal glyph.

There is one partial solution. If the glyph has the same metrics than another glyph (that is not a component of the glyph), then you can add a metrics key. It will be applied correctly. So you can link the left side of the e to the o and the brace layer if the e will get the correct spacing.