Go to any page and view the history (for example, https://en.wikipedia.org/w/index.php?title=User:RoySmith&action=history). Click to open the "Filter revisions" pane. Enter a year in the "To date" box. You should now have a calendar date picker on January of that year. Click the "1". The date picker will close and you'll be left with "No date selected". See attached screen capture:
.Dates other than Jan 1 seem to work fine.
I'm using Chrome Version 92.0.4515.159 (Official Build) (x86_64) on MacOS