Gutenberg: Block validation Failed Richtext undefined

I am building a custom block to add a youtube-video as a background-video that autoplays and infinite loops when you visit the site. To make this happen the user needs to get the video-link and playlist-link (for the loop) and put it into the 2 Richtext input fields I created in the block. Once that is done the video will start playing alredy in the backend to get a better view on how it will look on the site. Now when you save the Block the code will be generated on the frontend as expected but as soon as you refresh the backend page the block will be broken and the following message will be displayed in the console:

Custom WP Block using Inner Blocks crashes editor, doesn’t save content

I’ve finally gotten around to building a custom Gutenberg/WP Block for a project and it’s basically kicking my ass. Working with React, Node, WebPack, Gulp is all new enough to me so there’s a learning curve I have to deal with but the incomplete and inaccurate documentation from WP is making things substantially worse. (Their documentation still says to use wp.editor but reading through tickets in GitHub I learned that was deprecated and should instead be wp.blockEditor, as an example.)