For enterprise use, available search engines are wanted to be restricted and the administrator hopes to disallow installing of new search engines by users. In current Firefox we can do it by hiding "Add Search Engine" UIs via userChrome.css or something. After XUL is ended, we need something to alter it.

This is similar/related to the bug 1268401.

A sample plan of the API is here: chrome.extensions.lock() // disallow to install new addons chrome.extensions.unlock() // allow to install new addons This API should require special permissions.

Sorry, I wrongly posted different API idea... The idea for the search engines is: chrome.searchengines.lock() // disallow to install new engine chrome.searchengines.unlock() // allow to install new engine I think the API should control only for installations by the user himself, in other words, installation of search engines from addons (via another API) should be allowed. Or, these method may have an optional parameter to specify the level of restriction: only for users, or anyone (including addons). This API should require special permissions

We don't plan on this API in WebExtensions. Moving over to Firefox to see if that's something that would happen through configuration of other means.

Removing from webextensions-additional-apis, this belongs in some kind of policy system.