WordPress have an option to install a new plugins and themes to your dashboard and you can also upgrade it for latest release. If you don’t want anyone to install or upgrade your dashboard. Just check on the code below to disable it.
Code will block users from installing/upgrading themes and plugins through the dashboard. To do this add quick snippet to your
You can use this to avoid stealing your code by installing some backup plugins and to avoid unwanted upgrade on your website. Some upgrade may crash your websites, client unknowing will do this most probably you can prevent it by disabling your plugins and themes update.
For more reference check WordPress codex
Thank You !!