Can't edit pages since upgrade to 5.5.1

Permalink
After upgrading to 5.5.1 when I select a block to edit it the page goes grey and nothing happens. I have to refresh the back to get it back.

Tried the same on another site and it is fine. How do I fix this?

 
JamesJoy26 replied on at Permalink Reply
Ok it is something to do with the theme as if I switch to Plain Yoghurt it works correctly.

Currently using Diamond Theme.