I can also reproduce it. I don't think that the different characters are really different characters, just a different font. For example, the character ']' (right square bracket) looks like the character '#' in the font cmmi10, and that is the character that appears when it is highlighted.
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I can also reproduce it. I don't think that the different characters are really different characters, just a different font. For example, the character ']' (right square bracket) looks like the character '#' in the font cmmi10, and that is the character that appears when it is highlighted.