OverStrike control character

[abrahamgross at disroot.org]

Then theres no problem with the advance width changes that overstriking will do (e.g. l←m)

2020/06/16 午後7:02:02 Peter Constable via Unicode <unicode at unicode.org>:

> For most scripts-and for Latin or Greek script with any support for typographic features-the engine needs to resolve what are all the glyph IDs in a run before it can start determining advance widths / positioning. And to do the latter, it will start with default advance widths and positions for all the glyphs but then apply position actions that could revise any advance width or position.
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