If you didn't want to change from the stock theme you could create a background using the colour picker to duplicate the stock Moode one....then add a colour dot or number somewhere (maybe below the single/consume/repeat icons) for each players background....?
'1' in green. '2' in blue. '3' in chartreuse...... maybe not chartreuse... ;-)
'1' in green. '2' in blue. '3' in chartreuse...... maybe not chartreuse... ;-)
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bob
bob