Embed images in HTML

I was trying to use the great https://h5p.test.schulcloud-thueringen.de/content-types/sort-the-paragraphs component, but I realized that when I was customizing the component (after importing in moodle, I clicked on "edit H5P content") and copy/pasting images in the HTML, after saving the images would be removed form the HTML (see attachment for example).

After a discussion we concluded that this was an issue from H5P itself, and not the library, as H5P removes the images from the HTML.

So a few questions :

• Why can't we add images in the HTML widget? This seems like a pretty severe restriction, and inline images seems fairly straightforward to manipulate. Only a subset of tags are allowed but img is not in this list, why can't we simply allow this tag?
• Where can I report this issue upstream? I can't find any github repo that hosts the official H5P code, and the code is spead among hundreds of repositories/plugins.
• Is there any other existing html-like plugin that allows me to mix text, math, and images ?
• If I'm willing to develop my own extension, can I also write custom code to customize the component, including for instance graph/code/whatever editors? This way I may be able to avoid H5P's limitations for now. EDIT: found that I can use https://h5p.test.schulcloud-thueringen.de/creating-editor-widgets to create my own component.