Rated 5 out of 5 stars

It also works with Seamonkey 2.8 by modifying the install.rdf
Funziona anche con Seamonkey 2.8 modificando il install.rdf

This review is for a previous version of the add-on (0.5). 

Hi, thanks for your review. Would you mind opening a ticket at https://github.com/vanto/tb-personal-level-indicator/issues and adding the changes you made to install.rdf? I can then support Seamonkey in future versions out of the box.
BR,
Tammo