If these issues are not enough to deter you, this might: GmailWiz does not work with Gmail's new Compose feature. If you'd like to use it, you have to be using the old Compose, otherwise you'll be sending out blank emails left and right. Support may be added along with other features in the future, but all my attempts to contact the developer were in vain, and I failed to learn more about any future plans for GmailWiz, if any.
GmailWiz brings a bright idea to the table, and attempts to increase productivity by cutting the time you spend on repetitive emails. Unfortunately, as it stands, I recommend that you stay away from this add-on, and look for productivity elsewhere. The add-on is half-baked, and that's putting it mildly. Unless you somehow get it to work consistently, you'll be spending more time tweaking it and fighting with it than you would just writing the email yourself.
Note: The Download button takes you to the vendor's site, where you can install the latest version of the software directly into your Chrome browser.
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