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Go to the page where the images are attached. In the top right corner is a three dots button.
Click on the three dots button, then click Attachments,
You’ll be redirected to a page with a list of images. In there, you can add and edit labels!
When your images are labeled, you can use the "News Image Label" field to select the images. Those labels will be used on News Cards Configuration > News Image Label, and that way, select which image appears on your News Cards.
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