I use ConvertKit for newsletters. It's an email marketing platform. I important images into it to customize it. I can also categorize recipients if I want, say, donors, to get a different version. But it only uses images that I import. I can't change the images in it.
I use Canva too. I create basic templates where I can swap out pictures or change the copy easily. But once I download it stuck with that image, unless I go back and change it in Canva.
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Deborah Zahn
Executive Director
Remedios Cat Rescue
NY
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