In my three decades online, it has never occurred for me to try this, and I found it so delightful once I did – both Chrome and Firefox will quietly rewrite backslashes in URLs into slashes:

Not Safari, however, even though the URL living standard says it should.

I am very curious if the presence of backslashes in URLs is owing to Windows still showing backslashes in file paths, or just because people casually don’t see any difference between / and \, which are arguably both similar, and relatively alien in everyday typography. (“Solidus” is the proper typograpical name for this kind of a slash, partly to disambiguate it from all the other slashes with their equally fascinating names.)