Try adding define('CONCATENATE_SCRIPTS', false); to your wp-config.php file

just below the define('DB_HOST' line.

To do so, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel, and edit the file with a plain text editor.

https://codex.wordpress.org/Editing_wp-config.php#Disable_Javascript_Concatenation

Hi, I must give credit to this guy, James… He is a blessing! Truly… I got my content/editing my content back in admin area.

He solved a problem that had developed on multiple sites of mine, due to whatever reason.

Here is someone who had similar problem:

“I have tried everything and anything and I can not get the visual editor to show up. I have not changed anything and all that has happened is WordPress updated and a plugin updated”

Here is another guy who knows this trick:

https://wordpress.org/support/topic/wordpress-screen-options-dropdown/

Me: “So if you have a problem in your admin where you can’t see text and if you click in text area and all you may see is red squiggly lines then you may want to try the solution at the top of this post. If you have trouble reach out to me. Or if you are pressed for time you can try Fiverr.

I tried hiring someone on Fiverr and they wanted $5/site. Which if you know how to fix it once(it’s a relatively easy fix), it will save you $5 a crack or $5/site.

Personally if you came to me w/this problem I would say for $5 I would fix 2 sites 4 u.

Peace out,

Kel