I use it for something else. Rated 3 out of 5 stars

I have been looking for a way to strip HTML tags from quotes when replying and this addon is the closest thing I've found. I can view ALL my mail in plain or simple mode and then hit this button to see normal email when needed. When I press Reply, the quoted message is stripped and I am still able to use my HTML signature because I am composing in HTML mode by default. I wish I could view in HTML mode and reply with stripped plain text quotes, but oh well.

This review is for a previous version of the add-on (3.6.3).