Frames filling process has been improved.
Before improvement:
When some frame is selected it sends sequence of ':back' commands until its entry in
':hist' list is reached. Then these entry is parsed and local bindings info is retrieved for selected frame
This process is repeated for every selected frame
 After improvement:
 When some frame initiates process of sending ':back' commands, every output is parsed if needed,
 local bindings info is retrieved and set for intermediate frames. So if you select, for example, 4th frame
 (counting from top), 3rd, 2nd and 1st frames are filled too with their local bindings data