Steps to reproduce the issue

update joomla 3.4.8 to 3.5.1

Expected result

functioning within normal parameters

Actual result

buttons [save], [save & close], [save & new], [save as copy], [close] don't work in articles, though the [versions] button works, at least when clicked it displays [item version history] which is blank (saving history is enabled). also all the tabs like [publishing], [options] etc. have disappeared from the article view as well as buttons [read more], [article], [insert image]

System information (as much as possible)

PHP Version: 5.5.31-1+mh1
Web Server: Apache
Joomla! Version: Joomla! 3.5.1 Stable

Additional comments