Unable to edit post content

When I try to edit a published post in Firefox or Chrome, the content disappears and I am left with just a title. See video:

Post URL: DIY Electric Jerry Can — unfinished.bike

Unfortunately there’s a bug in the Rich Text editor where it can’t parse out HTML:

Looking at your post, I see <AT> near the end, which the editor is probably picking up as an HTML tag. If you put something else here (assuming to obscure your email address), everything should work.