#0001 Duplicate issues or followups
If your connection is slow or the issuetracker is slow it is sometimes possible to save an issue or a followup twice if you press the "Save Issue" or "Save Followup" twice. Prevent duplicates at all cost.
3 years and 6 months and 1 day old
Should work now but for followups it's different from issues.
For followups it only looks at the last posted followup (aka thread) and compares to that. If the last one was for example Open -> Completed then we can accept to identical comments. If the previous one was a followup and you post another followup with exactly the same comment the latter one is ignored in favor of the previous one.
If you do this: Open -> Completed and enter a comment like "test". Then hit Back and submit again. Then instead of setting the title of that followup to "Open -> Completed" again, it becomes a regular followup. (unless you leave out the optional comment which gets ignored)