When a file is uploaded as part of a form submission, its MIME is included. I've discovered that Firefox on Windows has an inconvenient way of determining this MIME.
The unstyled appearance of the WordPress comment box leaves much to be desired. Some CSS magic can make it look great on mobile and take advantage of available real estate on larger screens.
The short answer, it turns out that Axios knows what to do with a Buffer object.
I observed that embedded blog posts are no longer loading when the site is viewed with Chrome-based browsers. This is serious, and nobody seems to be talking about it!
At the bottom of it all, be aware of how the platform stores the app data. This advice helped me to debug a perplexing issue.