This is a quick fix release for 4.0.0 be sure to read 4.0.0 changelog:
Fixed :
Do not show the beta header in settings (It was just a display issue, 4.0.0 is a stable release build)
Missing resume button in some cases in album view.
Support a few more cases for embedded images in new custom tag parser.
Lyrics view now allow 1 empty line to better indicate pause when present.