I am still hunting for this error, because I cannot reproduce it myself, but I believe that I have found the reason (at least for my case, but I need to release it and see if it helps).
, , , , Handler ( , , ).
, onChange , .. onChange, , onContentChanged, , ... , cancelationTask (- ), , .
, , cancelationTask , , (takeContentChanged ).
, , , () (onStartLoading ).