Use case: I have a button that triggers a long-running process. I would like to add a spinning icon to the button itself to show that the process is already in progress (it has no reason to affect the rest of the page).
I can add an imageUrl on the fly, however when the process completes, I would like to be able to remove the image, and it does not seem to work. If I set imageUrl to null or empty string, nothing happens.
This is not a huge problem as I can write jQuery code to hide the image, I just wondered if there was a simpler way.