Typing and cursor freezes itself

Since some months, when I type in Scrivener the system stops itself and run something in the backgorund, waiting some seconds (1-2-3 seconds) with the color route, and then I can continue.

I tried to put autosave to 40 seconds or 2 seconds: nothing changes.
I don’t have images: it does this in a fresh scrivener file.
I don’t have text expander or stuff like that.

I noticed that the “bug” appears especially in the FIRST character of a line.

If I’m at the beginning of a line and i press a key, for example “s” and then i try to delete it, the system freezes itself for some seconds.

If the character I try to delete is the second of the line it doesn’t freeze.

Some months ago Scrivener worked fine.

other very strange thing: the freeze often appears if the character i write is “s” (italiano keyboard)

absolutely strange