Rated 3 out of 5 stars

I'm giving a good 4 star review, because I don't know that this extension is the problem for sure. I have the following problems:
- Tons of drafts saved with the original "conversation" in Gmail (although not in Thunderbird)
- Missing email, although I can find those messages using the web interface for Gmail.
- Although copy-sent-to-current, a copy is made in the sent items folder anyway. When I use something other than Thunderbird with this extension, a reply copy is not made to the folder/label of the message being responded to. That means I don't know which messages in the sent items folder I have copied to the corresponding folder/labels and which I have not.
I really had high hopes for this extension. And now, I believe TB3 added the option "place replies in the folder of the message being replied to", making this extension relatively superfluous.

This review is for a previous version of the add-on (0.9.5).  This user has other reviews of this add-on.