How to upgrade the editor bottom bar on xwiki 10.4 to 10.5 flavor

Hi, I want upgrade my XWiki(10.4) editor bottom bar to 10.5 flavor.But not necessary to upgrade XWiki(10.4) to 10.5. Is it an extension?
it is the XWiki10.5 editor bottom bar from the XWiki 10.5 release notes:

No it’s not. You need to upgrade, sorry ;). BTW you should upgrade to XWiki 10.7 just released yesterday!

Ok!Thanks ,I will upgrade it later.
And I have another question .
When user open a edit page ,I want the Autosave could enable by itself.How to configure it or do something?
image

I’ve just googled and the first hit led to https://dev.xwiki.org/xwiki/bin/view/Drafts/SetAutosaveOptionIsTrueAsDefault

However I don’t recommend doing this. Autosave creates a lof of revisions which will make your wiki become slow relatively quickly. In other others autosave is not mature enough ATM.

OK!Thank you very much. I will think about it.