Category page: Prestashop doesn't update description when save it

[3msweb]

hello everybody, 

I have a problem that is driving me crazy. 

I have prestashop 1.7.8.6 and I have 2 languages installed, ITA and ENG. 
If both are active, when I go into a category and change the description, Prestashop tells me it has been saved, instead the changes have not been made.

If I disable the ENG language, I can edit the category description, clicking save Prestashop applies the changes, but leaving only one language active (even deleting it) I have problems in the front office, when the user enters the cart and clicks on checkout the page does not update and the site registration page is not shown. 

To remedy this problem I re-enable the second language, so the checkout is working again, but the problem that I can't edit the category description comes back 

When I do these tests, I also clear the cache and force compile, but nothing. No solution.

Can you help me?

 

Edited August 8, 2022 by 3msweb (see edit history)

[3msweb]

I don't know if it is useful, but when I enter in a category page I have this message:

[Error] TypeError: null is not an object (evaluating 'tinyMCE.activeEditor.getBody().textContent')
    value (category.bundle.js:87:7281)
    (funzione anonima) (category.bundle.js:87:4942)
    (funzione anonima) (Elemento script 1:2:197011)
    fire (Elemento script 1:2:197537)
    load (Elemento script 1:2:347095)
    bw (Elemento script 1:2:328173)
    ww (Elemento script 1:2:330249)
    (funzione anonima) (Elemento script 1:2:333554)
    (funzione anonima) (Elemento script 1:2:96974)
    jt (Elemento script 1:2:29361)
    u (Elemento script 1:2:96917)
    n (Elemento script 1:2:96404)
    (funzione anonima) (Elemento script 1:2:96654)