After I edit a question before, it said something like 'It has to be approved before it is reflected. The edit is only available to you'. But, now, it doesn't show anything, and the edit that I made is simply cleared. Was there a change on the system, or is my edit rejected automatically, or what?
Your edit seems to get rejected.
Probably, people think just removing salutation, is not really useful edit, so your edits got rejected. once you hit limit of rejected edits, you will lose edit right for a week (may be), so please take care with that.