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All other symbols accessible by AltGr (e.g. I realized after updating Windows 10 (Education) from 1909 to 2004 that the µ (AltGr+M) keyboard input no longer does anything, as if no key was pressed.
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This is common for other languages as well, which use extended alphabets. I'm using a German keyboard, which has an "alt graph" key (right alt key, or AltGr) to access a tertiary symbol on certain keys (in addition to a secondary symbol accessible by the shift key), for example (AltGr+Q), € (AltGr+E) or µ (AltGr+M).
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