If I type in <figure><img src="my-source.png"><figcaption>My caption</figcaption></figure> into the editor's source code, and save, re-opening the editor then shows the code as <img src="my-source.png">My caption. How can I prevent Moodle messing with my source code?
That is a question... you can try and turn off HTMLTidy... but that doesn't always work. Better option so far is to put the caption into the image, using Photoshop or GIMP or your favourite image processor. Painful and is being worked around but I have yet to hear of success here,,,,