I noticed that behavior too, @Thraeg.
BTW, now the Cannot Load App message in Firefox 59.x is replaced by:
Corrupted Content Error
The site at The American Dark Age (2016-2020) An archived history of the worst President ever - #14823 by RichVR has experienced a network protocol violation that cannot be repaired.
The page you are trying to view cannot be shown because an error in the data transmission was detected.
May 9th can’t get here soon enough.