I am encountering a repeated problem making online reservations in another country through Firefox, in which I select the correct date in the displayed calendar, submit the reservation request, and then receive a confirmation for the day following the one I requested. It has now occurred multiple times in the last few months, involving reservations made at hotels, restaurants, and libraries through a variety of platforms (third-party consolidators, directly through the business's own site, etc). I thought at first it might have to do with the time zones--I made the first batch of reservations in the evening US time when it was already the following day in Europe, but it is now happening with reservations made at a time when the dates match. When I contact the businesses, they see no sign of error on their end. I feel like I am losing my mind.