M-x bongo-play-next in ordinary buffers changes header line

[xuchunyang]

For example, run M-x bongo-play-next in *scratch* will add a header line in the buffer, I expect only the header line shows only in *Bongo Playlist*, according to

bongo-header-line-mode is a variable defined in ‘bongo.el’.
Its value is t

Documentation:
Whether to display header lines in Bongo playlist buffers.

You can customize this variable.