Was just checking the error logs on a new install of 5.4.1 and see a lot:
Got error 'PHP message: PHP Deprecated: media_buttons_context is <strong>deprecated</strong> since version 3.5.0! Use media_buttons instead. in /var/www/susites/evozyne/htdocs/wp-includes/functions.php on line 5088', referer: https://evozyne.highgatewebworks.com/wp-admin/post.php?post=8&action=edit
I can't find any mention of this anywhere except in an old WordPress Core discussion.
Can anyone shed some light on this?