When creating an In-App/Pull Message in Carnival, it is important to take file size into account. As a best practice, the smaller the image, the more successful we find the In-App Message to be.
Currently, Our file size limit for image is 10MB and there is a 50 MB limit on the file size of videos. Be aware that large files will take longer to load and display/play for your users, potentially decreasing the views. Users on cellular data with limits are also worth considering.
If you find that you are unable to Save and the screen hangs on "Saving", this is often the cause: