Fixed
- Unticking a recurring task left the series looking doubled. Marking one off creates the next instance, but that instance carried no trace of where it came from, so taking the completion back - the natural fix for an accidental tap - reopened the task next to the instance that same tap had created. Two entries for one series, and the only way out was deleting one by hand. Moving a task back out of "done", by checkbox or in the edit dialog, now withdraws the follow-up it created. Only an untouched one: a follow-up you have since completed yourself, or given subtasks to, stays put, because a click on its predecessor must not throw that work away. Ticking the same task off twice no longer adds a second follow-up either.