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Gmail's recent email rendering change
Gmail recently made a few changes in their email rendering engine. Unfortunately for us our image based HTML newsletters that used to look fine in gmail are now broken. Each image seems to have a weird spacing after it.
If you’ve been sending HTML newsletters for your clients for some time now, you probably have your own email templates that work well in all email clients. Well not anymore thanks to Google.
To make things back to what they were just add
style="display:block;" to every img tag in your HTML email and we’re back in business.