I noticed a article by HowToGeek which said that you can automatically display lyrics for for music played on Jellyfin. Until now I only used Jellyfin for music but I thought this was worth investigating.
First I added a new Jellyfin library for Music (I only used TV Shows and Movies previously) containing some sample music. This allows me to select and play albums in the same way as films.
Jellyfin has a plugin, sensibly called Lyrics, which will try to find suitable lyrics and associate them with a song. You schedule a job in Jellyfin to regularly search and add lyrics.
I linked the Jellyfin music library to my NASmusic database so that I can play anything with Jellyfin.
Both the PC and Ipad standard Jellyfin Music Apps display the lyrics properly.
Lyrics are taken from lrclib.net, a wonderful open source database. It turns out that if the track duration is not within a couple of seconds of the one in the database it will not sync but plain text is displayed.
If the name / details of a track are incorrect the database may not be able to find the music - I expect this can be fixed my correcting mp3tags.