Bug in calendar, only Safari

On older dates like the year 1977 the calendar has a bug, in Safari it shows wrong, it differs one day.

Framework7 v5.7.5
Central European Summer Time
Time zone (GMT+2)

See screenshot.

There is another bug in the demo:
Try to browse from the month september to october in the year 1977 in Safari, it goes to november.

No one has looked at these 2 bugs?

@nolimits4web could you have a look at these issues please? Thx!