"Only quote selected text when replying" feature not working in Kmail

[Matt Connell]

Apologies if this is not the correct place for this posting.

When I enable the "only quote selected text when replying" feature under 
Configure -> Composer -> General, the reply behavior doesn't seem to change.  
That is to say, if I try to select a line of text, and reply (as one would do 
with a mailing list, for example), the reply window quotes the entire message 
instead.  I've tried unchecking and rechecking the box, with an 'apply' in 
after each change, to no avail.

Is this a bug?  How can I troubleshoot/fix this?

Kmail Version 5.13.3 (19.12.3) (according to the about panel) on Gentoo Linux, 
with OpenRC profile selected.

-- 
Matt
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