The date accessioned flatpickr on additem.pl should not allow dates in the future.
I wonder if there is a use where this would make sense. Maybe for "on order" items?
I can see an argument made for the case that Katrin points out, so I've amended the title of this bug to "Item date accessioned should (optionally) prevent future dates." I ran into this as an issue when I recently had a library running a report looking for items added between January 1, 2020, and December 31, 2020, and some items they expected to seen on that report didn't appear on that report. After some investigation I discovered that items they were concerned about had dates in the 952$d that are still in the future even though they added those items about 5 years ago. On some of those items it looked like someone probably scanned a barcode when the cursor was in the 952$d input. I don't remember when flatpickr was added to Koha, but I think this all happened before flatpickr. When I investigated further, I found that we had about 100 items in our system at different branches that had future dates in the 952$k. Some of these dates were a few months in the future; some of these dates were centuries from now; some of these dates were eons from now. I have actually cleaned most of them up, but I'd like to be able prevent staff at our libraries entering 1/12/7788 as the accessiondate of an item until we are at least a little bit closer to 7788. So for the purposes of my system, I'd like there to be an option to set the flatpickr in the 952$d so that it disallows future dates.