Hi again,
Today I formated one of the laptops whit this problem. I perform a fresh install of Ubuntu 22.04.1 LTS and install tha Brave browser from snap.
sudo snap install brave
In these laptop the open/save files is normal. The browser does not freeze when i save files from the same sites then before.
The problem is now in other 4 laptops. Maybe a package incompatibility.
Regards.