GMail shows confirmation email button with blue text on blue background #2832
Description
Observation
In GMail, I got a confirmation email looking like this:
The confirmation button appears only as a blue text, as GMail renders the label in blue on blue background. In addition, GMail didn't show the embedded logo that I had configured. A warning was shown that GMail had hidden embedded pictures.
After hitting the "Show pictures" button in GMail, the button appeared as intended like this:
So it seems that in "pictures hidden" mode, CSS is also not applied (at least in parts).
Solution
An alternative would be to use a different button background color than blue.
An even safer alternative would be to avoid a button and instead show a plain link, like this:
Some spam/phishing filters consider this more safe for users, as the URL that will be visited is immediately visible. This would increase the likelihood of confirmation emails reaching the users inbox.
Another improvement could be to avoid sending logo or any referenced images in transactional email (or at least in the subscription confirmation).