debug visualizer doesn't get frame id correctly when selecting frame from call stack

[ono-max]

Sample script(Ruby)

a=1
def foo()
  a = 3
end
foo()
puts a

When I select frame id, which is the location of the caller of function foo(), I should get the value of a(which is 1), but I can't get it in debug visualizer. It would be great if we support it.