If you wish to add rounded corners to an image in Learnifier (either in an activity or in an email template), you must first add the image as a URL.
Add a new text component and click on the image icon in the grey menu.
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Add the URL and click OK.
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Click on “Source” in the grey menu.
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In the style tag, add the following:
border-radius: 25px !important;"
The final code should look like this:
<p><img alt="" img="" src="{image url} " style="width: 100%; height: 100%x; border-radius: 25px !important;" /></p>
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All done!