TIL that all some UNIX based systems have a Y2K38 superbug in which the number of seconds that have elapsed since the Unix epoch began (Jan 1, 1970) are stored as a signed 32-bit integer which maxes out on March 14, 2038.

I suppose Proton Calendar is just using a generically premature cutoff because reasons. Unfortunately experts report no known solution to this problem and we will very likely be without computers after this date.

Edit: The recent discovery of signed 64-bit integers (as published in PNAS) will now allow us to kick the can down the street an additional 292 billion years until overflow. Unfortunately, this only delays this apocalyptic problem for a mere 21 times the age of the universe.