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Edit the playlist columns, or create new playlist columns in Preferences > Display > Default User Interface > Playlist View.
See the Playlist View wiki for description.
For example, a normal 'Title' column is like this -
Name: Title
Pattern: %title%
Instead, use a pattern like this -
$if(%isplaying%,>>>%title%<<<,%title%)
After you make the column, you must add it to the playlist by right-click column header > Columns > 'Title' (the custom one in lower menu) - and de-select the default column.
Note: the highlight is only shown when the playing track is not selected. When it is selected (or using 'Cursor Follows Playback'), the background uses 'Selection' color and text is black/white. Edit: other Playlist Viewers might do things differently.