If you add a space before a link in the link URL field, it turns out Marketo will just leave it there. This can happen accidentally when pasting a link from another source. The resulting code inside the email looks like <a href=" https://examplelink.com"> with a space between the opening quote and https.
If you click the image either in the preview or when the email is sent, it actually works just fine. But when preparing the email for send, Marketo doesn't recognize the link as a link, and therefore doesn't create a tracking link. The effect is the same as if you had included the entire link, http and all, inside a token: the link is functional, but you lose all tracking on it. This ends up being a mistake that's easy to make and hard to catch.
The simple solution would be to add a function - like you see in many other input boxes - to automatically remove any leading spaces in that field. This would be a nice little failsafe that would prevent a mistake you would likely only catch when higher-ups are demanding a report from you.
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