Use Rich Text to Markdown converter in WYSIWYG editor

That's a huge issue that I can't just copy-paste text with formatting (Rich Text) in Joplin – it looks just as where I copied it from at first, but after I reload the note, it's just pure text without formatting.
I googled and find just in the first place the open-source tool that can Convert Rich Text to Markdown and it works very well! Can you please embed it in Joplin?