Developer reply by Łukasz Nojek
Rated 4 out of 5 stars
Adding support for GMail Labels to Thunderbird offers a useful benefit to anybody that has set up rules on the Google account side, rather than in Thunderbird. It is very useful to be able to confirm the expected labels are attached.
The only significant usability issue that I have come across so far, is that you only see all of an e-mail's labels if you have gone into a folder to open the e-mail. If you access it directly from the Inbox initially, you will only see the Inbox label, suggesting the message has no other labels attached. So you have to be aware that an e-mail may correctly have the labels you expect, but you have to open it at least once from one of the (label) folders before they will show up.
Only other feature I would like to see, is labels being presented in the label colours set in the Google account.
Other than that, it does exactly what it says on the tin, quickly, and without fuss.
Thank you for your review. As for the issue of missing labels when you open a message directly, that's because labels are not part of a message, they are associated with the folders in Thunderbird that contain copies of the message. So until your Thunderbird refreshes all folders, the information about labels will be incomplete.
To create your own collections, you must have a Mozilla Add-ons account.