Thanks a lot ! I have found what was the problem : on Firefox I use Duckduckgo Privacy Essentiels and I think there are trackers of AddToAny site in the code so it was blocked.
I will try the others plugins without this extension and maybe it will be better.
For example with FootNotes and ImageGallery Pro.
Sorry for the inconvenience... I will inform you of the results.
Best regards.
Nath