I found that the reason for the problem is the possibility a few characters or more might be caught by the CENSOR filtering and converted to * characters.
There is no control as to what the encoded characters are. It is, after all, the base64 encoder.
I have one work-around (I have more than one, but this I find easier) where I look for the result of any * character in the forum "preview."
If a * is there, I re-edit to place a " " (space) character after the first offending character, then preview again. And check it again.
The receiving person needs to remove that space (it is easy to find), before it is saved on their local drive as some .b64 file.
Really clumsy.
I was playing with (in the Test forum) a method of attaching a file. It almost works, but there is still a problem with that work-around. Plus, that work-around is clumsy and probably has limitations I haven't even fathomed yet.
How about an ability to add a file with general controls?

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