widgets sidebar disappeared after update 4.2.2

What sidebar and widgets are you referring to?

I am referring to the admin dashboard: when i choose the option Widgets all i see is the text ‘Available Widgets’….. the widgets themselves are not visible.
Yesterday i’ve installed WP again and then everything seemed to be fine, after pushing F5. Now the widgets are gone again.

This problem started after i have tried the Customizer in the new WP.

sounds like the problem i just described in

https://www.ads-software.com/support/topic/widgets-page-not-displaying-properly-non-functional-1?replies=1#post-6929108

the usual page is still available via the dashboard: Dashboard/Appearence/Widgets thankfully

Nope, my problem is another problem ??

My problem started after trying this new Theme Customizer WP offered in the last update. With that new tool I have tried to change themes (which didn’t work) and trying that it seems that action has messed up some dasboard functions…like not showing the widgets in the Dashboard area.

It seems the problem occurs with the Display Widgets plugin.
It seems the developer has to made an update.