Cannot open "plugin" and "theme" tab on admin page

I cannot open “plugin” and “theme” tab page on the admin page. I upgraded my grav page to 1.4.0beta1 from 1.3.10.


An exception has been thrown during the rendering of a template ("Not Implemented").

I tried clearing the cache.
Should I wait for admin plugin or grav version upgrade?

According to this page, I solved it.
Grav 1.3.9 causes GPM Issue, 1.3.10 Fixes | Grav :