Save key in sessionStorage for easy repeated visits during the same session

[Greenheart]

How it should work:

On DOMContentLoaded:

if sessionStorage.key:
  try decrypting (call decrypt as if the user had submitted the form immediately on pageload)
  if successful:
    show result
  else
    show regular password prompt like nothing happened

After successful decryption:

sessionStorage.key = key

then continue loading payload like normal

[Greenheart]

fixed in 4.0.0