How to tell GUI MUAs to show message in a fixed font?

[Grant Edwards]

Is there anything one can do when sending a plain text e-mail message
to tell GUI-based MUAs that they should display it in a fixed font?

I would have sworn that a lot of GUI e-mail programs used to use a
fixed-width font for text/plain content-tupe, but they no longer seem
to do that.

-- 
Grant Edwards               grant.b.edwards        Yow! TAILFINS!! ... click
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