areyouheartbreaker

take a look at your theme code. maybe your jquery script conflicts with other libraries

check this https://www.ilertech.com/wordpress/whats-wrong-with-the-wordpress-redirection-plugin/

i remember someone posted this link here

just quick update, i fixed it by turning off magic_quotes_runtime setting

try to reupload fresh-new wp-includes & wp-admin folders. i had the same issue