Metrics don't sync properly

This has been bugging me for ages in several different fonts.

Here I want to sync the lsb and width of ra-myanmar with wa-myanmar. Here I haven’t synced it yet, it’s 10 units too wide:

When I hit cmd-ctrl-m, the width syncs but the lsb is now incorrect.

Clicking either of the ↻ update buttons syncs that value but unsyncs the other one.

It works for me. What version of Glyphs is this?

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