Thread:Project:Support desk/Recent changes/reply (11)

The only "danger" in using an extension that uses a deprecated hook is that, if you upgrade MediaWiki to a newer major release (let's say MediaWiki 1.23 to 1.24) and the hook is removed on that version, the extension will no longer work. In the case of hooks, it won't produce any error, but MediaWiki won't call it anywhere.

Note that deprecated hooks, method, etc indicate that an alternative exist, and code should be modified so it will work properly on newer versions, but those hooks doesn't necessarily need to be removed on the next release. They may (or may not) last several new release without being removed.