Unsupported characters in content results in invalid json.

[BigBlockStudios]

Unsupported characters in content results in invalid json editor won't load. In my case this was caused by a collation/character set mismatch while uploading a database.
If these improperly encoded characters are in the page content - the editor won't load on the front end with a

SyntaxError: JSON.parse: unexpected end of data at line 1 column 1 of the JSON data

error.
You get the same error if you create a new page but any elements containing improper characters will cause the editor to display
"SOMETHING WRONG HAPPENED"