Get blank page - can't upload h5p file in Joomla
So I've seen a couple posts on problems using H5P in Joomla. I installed it to make flashcards on Joomla 3.3 site. When I create new article and click on h5p button, I get a popup that is completely blank - no way to upload anything. Does this mean the component is not compatible with Joomla 3.3, or is there something else wrong that I can fix? Has this happened to anyone else?