WordPress 4.9.8 doesn’t save if content has style=”

I’ve had the same issue recently.

Inline styles, as well as <img> tags, would cause the 410 Gone status and error message (The requested resource /wp-admin/post.php is no longer available on this server and there is no forwarding address. Please remove all references to this resource. upon previewing or publishing the post.

The problem was due to the hosting provider doing some maintenance on mod_security in cPanel.

I found out when I asked them for the Apache logs so that I could look into it more.

Contact your hosting provider to get this fixed.