I need to write a customized Jalview annotation to colour (for example in green) different positions for each sequence_id (on each row). I need an example (I've already checked the doc). Help, Thx.

For example:

1abc 15 30 green

Residue in positions 15,30 colored in green

I've tried writing a GFF file or a simple text file with \t but I didn't succeed.