WordPress 4.2.1 editor slow to load

After installing 4.2.1 and updating the database, the wordpress editor takes close to one minute to load. I tried going back to default 2015 theme and disabling plugins (both through admin panel and FTP) but that didn’t fix the issue. All other admin functions work without lang the issue seems to be only with the editor.

can any one find a fix for this

Thank you