The "New event" button in the day view seems to not work intermittently. If it works, it opens the "New event" creation page instead of the "New event" modal.

To reproduce:

1. Go to calendar/view.php?view=day
2. Click on the "New event" button.
3. Expected:
   • The "New event" form modal comes up.
4. Actual
   • The "New event" creation page comes up.
5. Click on the back button of your browser.
6. Click again on the "New event" button.
7. Expected:
   • The "New event" form modal comes up.
8. Actual:
   • Nothing happens