Hi, The problem is that I am using the version of Lilypond supported by the OS package manager. I'm running Pop! OS which is basically an Ubuntu derivative. They JUST today announced their next LTS release (22.04) is ready.
So, the OS maintained version is currently at 2.20 (to be precise, lilypond 2.20.0-1). If I explicitly use the URL for 2.20: https://lilypond.org/doc/v2.20/Documentation/learning/ and use the search at the bottom of the green sidebar on the left to search, let's say for "slur", the page that is returned is the Google result page. However, it shows that Google is searching for "site: lilypond.org/doc/v2.19 slurs" -- i.e. though explicitly searching from 2.20 "tree", it returns a result for 2.19. I can't cite other examples immediately, but as I recall, it sometimes goes back to 2.18, sometimes forward to 2.21, etc. I never know if the search returned is going to give me documentation for the version I have installed.
