Calibre Forgets Search Preference

I normally disable (and leave it permanently disabled):
Preferences -> Searching -> Highlight Search Results Instead of Restricting the Book List to the Results

Periodically, however, Calibre "forgets" this setting and reverts to highlighting results. If I check preferences, I find the checkbox checked.

This behavior seems to have started after I began using "Saved Searches".

Is this a bug or am I doing something wrong?

Note that I'm on 2.57.1 (Win64).

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