Different but related, 46 BC, the year of adoption of the Julian calendar, had 15 months [2].
[1]: https://en.wikipedia.org/wiki/Adoption_of_the_Gregorian_cale...
IMO, this list is only good at... wasting time. Except for the multiple statements (that could be one or two) that point out that there's not such a thing like "identical clocks" and "same time on two clocks".
The daylight savings time transition doesn’t “shorten” or “lengthen” the day, it merely transforms the clock. The day isn’t 25 hours or 23 hours. This is essentially the same thing as the Julian/Gregorian swap. The day didn’t really change, just the system we use to understand what day it is.
The span of time users experienced was weird, but this wasn’t the unit of time being shorter or longer. It’s an artifact of the transition not anything happening to the time.
A lot of these falsehoods on the list can be side stepped by distinguishing between the dimensions and the facts about representing time.