Karaoke-style lyrics in iTunes I would like to have iTunes display the lyrics while playing and auto-scroll to synchronize with the audio.  I am willing to add ID3 tags or XML or some other such thing to lyrics to support the sync, but I am not aware of a format/syntax to do so.

“Cover Version” will display the lyrics (and any embedded codes) but no auto-scroll (and it is unsupported since Yosemite and iTunes 12.6.1)

Get Lyrical and LessLyrics sound useful, but I would really like to do it in a visualizer in iTunes on both iPad and MacOS.  And neither (nor "Get Lyrica") is in the app store.

As I was typing this, a couple of possible duplicates appeared in the "similar questions" list, but just as I was about to click one, both links disappeared!
Looks like LrcShow may do the trick. There are full usage requirements and instructions on that page, but it seems that it supports live lyric display for lyrics with bracketed timecodes before each word (.kra), before each line (.lrc), or a static display for lyrics with no timecodes (.txt).