All is in the title, you will find below a video example : first try with a category with acrute accents "Etanchéités" (not working) and second time with a category without accent "Sols techniques" (working).
Maybe it happens with others text accent in french like "à", "â", "ê", "ë", ...
I haven't try yet.
In a first time I will put uppercase texts with no "é" accent to solve the issue for this customer.
TIA for your investigation. :-)