Gutenberg copes with the embedding of Gist URLs, in the fact that they work, but output in the editor is blank. This makes any kind of editing difficult.
Here's an example of a Gist URL for demonstration - https://gist.github.com/dartiss/028c0065c06b0b84a26f40038fbf47b7. Create a new block and paste this on. The resulting block will be black, albeit editable (to an extent) - if you view it as HTML you can see the embed. Previewing and, ultimately, viewing the post will show the embed correctly.
Gutenberg copes with the embedding of Gist URLs, in the fact that they work, but output in the editor is blank. This makes any kind of editing difficult.
Here's an example of a Gist URL for demonstration - https://gist.github.com/dartiss/028c0065c06b0b84a26f40038fbf47b7. Create a new block and paste this on. The resulting block will be black, albeit editable (to an extent) - if you view it as HTML you can see the embed. Previewing and, ultimately, viewing the post will show the embed correctly.