Hello Everyone,
Is there any way that we can have a text on the image.
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It is possible for billboard images, but if you are asking regular image No, I you want you can add caption to that image which shows when user mouseovers on that image.
Check the below links and you will get some ideas.
https://docs.appian.com/suite/help/22.1/full-overlay.html
https://docs.appian.com/suite/help/22.1/ux_billboard_layout.html