I recently installed a new version of Mathematica and it includes an optional companion package entitled "Wolfram Extras". Is there any official documentation (release notes?) that details what programs, packages, or functionality are installed by this optional component?
After installation of 10.2, the Mathematica preferences dialog displays the following listing (next to the button "Install Wolfram Extras"):
Wolfram System Browser Plug-in
Not InstalledNotebook Indexer for Windows
Not InstalledNotebook Indexer for Google Desktop Search
Not ApplicableNotebook Indexer for Copernic Desktop Search
Not Applicable
The comments from user @Lou on this related question (78536) mention some of the things past "extras" packages have included:
[functionality] that allows you to view CDF documents when embedded in web pages and preview notebooks in your web browser.
Browser Plugin and Spotlight Plugin.
UPDATE: In Mathematica 11.1 the "Install Wolfram Extras" button as well as the information about installed Wolfram Extras is removed from the "System" tab of the "Preferences" dialog. In version 11.0.1 this information is available.