For development purposes I transferred site to local WAMP server.
On frontend all works fine.
When try to edit widget content, it reports error: "ReferenceError: proofread_botCore is not defined". When error window is closed, editing is possible, and save too.
Same error also appears when new widget is placed.
Nothing serious, but bit annoying and time wasting.
Works nice with WPML as 3 different widgets with language condition.