Daylight Saving Time stats Calendar bug: also depends on current date, not just current time

It is now April and there has been a slight change in behavior, see below.

  • Version 24.04 (429bc9e)

  • Qt6 on Windows 11

  • Computer uses a North American time zone that observes Daylight Saving Time

  • Whenever the current time of day falls precisely within the one-hour time interval immediately after Anki’s “next day starts at” changeover hour (by default 4:00 am to 5:00 am), then when clicking Stats to open the Statistics window for any deck, in the Calendar section the little square for March 10, 2024 (which was the Daylight Saving Time changeover date in North America, namely the second Sunday in March) displays as white and a mouseover over it shows 0 reviews. At any other time of day, that square is blue as expected and mouseover shows the actual (non-zero) number of reviews.

Original report for 24.04rc2 (when the current date was in March 2024):

  • The little squares for the Daylight Saving Time changeover dates of previous years (2023 and earlier) do not show this behavior either for the March switch to daylight time or the November October switch back to standard time.

What is happening now (the current date is now April 2, 2024):

  • The little squares for the Daylight Saving Time changeover dates for March of previous years now do show this behavior (for March 8, 2020 and March 14, 2021 and March 13, 2022 and March 12, 2023, in addition to March 10, 2024).
  • They still do not show any similar issue for the October switch back to Standard Time. Those dates are October 25, 2020 and October 31, 2021 and October 30, 2022 and October 29, 2023.



I temporarily reinstalled 24.04rc2 (b84fce4) to make sure that the changed behavior is due to the change of the current month from March to April, and not the change from 24.04rc2 to 24.04.

Tracking issue: Due counts on calendar graph can change after midnight · Issue #1025 · ankitects/anki · GitHub