there is another problem when the plugin is enabled, I can't delete users osclass v4.4.0

If you open struct.sql, foreign key is not written properly and is blocking user removal:
    FOREIGN KEY (fk_i_user_id) REFERENCES /*TABLE_PREFIX*/t_user (pk_i_id)

Correct should be something like:
    FOREIGN KEY (fk_i_user_id) REFERENCES /*TABLE_PREFIX*/t_user (pk_i_id) ON DELETE CASCADE ON UPDATE CASCADE

Note that after change, you must reinstall plugin.

Found the reason, the photo in the profile is not displayed, I have a plugin installed for registration via social networks, when registering a user via social networks, there is no photo, how to put a stub "no avatar" Please help me solve the problem

I suppose plugin does not feed these data from network and social plugin does not upload picture to avatar plugin.
Anyway it should show some default image and is definitely issue of plugin.

can you make sure that when a user is registered via social networks, he receives a picture "without an avatar"? and how to do it?.

That is bit complicated and social networks plugins should handle it, but they will not do it definitely for all the profile pictures.
Better way is to update to osclass 4.3+ and rely on built-in profile pictures.

I do not want to receive images of users from social networks. I need an "avatar plugin" to install a "no avatar" stub when new users register via social media on the site. Could you help me with this please?

I do not think I understand your question, but we've updated Avatar Plugin to v1.2.1, update, test and then let us know if something else is needed

I do not think I understand your question, but we've updated Avatar Plugin to v1.2.1, update, test and then let us know if something else is needed

You are simply the best developers! Thanks so much for your work, quick replies and quick fixes

Ho ho hooo, marry xmas 

In your personal account, when uploading a photo, you can upload any files, exe, php. how to make a restriction so that the user can only upload jpeg and png files