I remember that someone from WRI stated in the official newsgroup that Mathematica 7 still has a working old-fashioned Mathematica Help Browser from Mathematica 5 for compatibility purposes. But I can not find the post where the code for invoking it is given.
How to invoke and use this legacy Help Browser in new versions of Mathematica?
The old browser will show up if you try to look at documentation for packages that were written in the old format. From the main documentation page, click 'Add-Ons and Packages' at the very bottom-left, and then click on the old package name. Based on what I have installed, it looks like the old packages will have a little orange square in front of them, instead of a triangle that shows/hides additional information.
The old browser is only used for old documentation.
I assume you're aware of the 'Function Navigator' and 'Virtual Book' which provide alternate ways of navigating the new documentation.
At this moment I have found two ways to invoke the legacy Help Browser by clicking a button:
and
I found that we have the global option
HelpBrowserSettings
that specifies settings for the legacy Help Browser.And we still have working functions
HelpBrowserLookup
andHelpBrowserNotebook
(now undocumented) and commandFrontEndTokenExecute["RebuildHelpIndex"]
for rebuilding the help index of the legacy Help Browser.