[kovidgoyal]

@arspr: yes, you are right in that the trailing checkpoints beyond the current one should be removed when you edit. They are currently removed if you use any of the automated tools, but it should also happen when you edit manually. That will be in the next release.

EDIT: However, when I tried to actually implement this, I found that there is no robust way to implement it. The contents of an editor can change because of many different user actions, it is not possible to keep track of all of them let alone decide which ones actually constitute a change or not. SO I'm afraid the trailing checkpoints will have to remain.