I have made a correction to your comments in:

ow_plugins/mailbox/views/components/new_message.html

since it makes HTML validation to fail due to the continuous dashes in the comments. In XML this is not allowed: <!-- -------- COMMENT ------- --> whereas this is ok: <!-- - - - - - - COMMENT - - - - - - -->

Please consider amending so that these changes are not lost each time the plugin is updated. 

Thanks