Assegnate 4 su 5 stelle

This add-on seems to do exactly what I am searching for, but why does it require "full, unrestricted access to Thunderbird, and your computer"?
Deal-breaker for me, unless there is a pretty good reason.

Edit: thanks for your fast answer. I may reconsider.

Please read https://support.mozilla.org/en-US/kb/permission-request-messages-thunderbird-extensions#w_have-full-unrestricted-access-to-thunderbird-and-your-computer