Value cannot be null. (specific string in specific path)

This morning, I needed a search in a specific folder "GS" (on a local volume). I typed the name of that folder in the field path, and I typed the string "message" in the search field. I then got the error message "Value cannot be null" and X1 had to close.

I tried it again. Many times, with different strings. As it happens, X1 can't handle certains strings within that folder. Il can handle anything in all my other saved path-searchs, and it has no problems in "GS" with "ABCD", "bahnhof", "boxe", "perte", "mastic"... it shows the results as I type and everything's fine. There's something (at least) with "message", though (and only in path "GS"). If I type sloooowly, I can get up to "mes", then X1 crashes with "mess".

Any idea?

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