Archival Format download may lead to license acceptance pop-up with guestbook text and no buttons

[janvanmansum]

What steps does it take to reproduce the issue?

Create a dataset with tabular files and make sure those are ingested. Set the license to something other than CC0 to make sure the downloader has to accept the license. Make the files non-restricted.

1. Log out.
2. Go to the dataset.
3. Select Access Data -> Archival Format
   
4. A pop-up appears
   

Note the extra text pertaining to a guestbook (which does not exist) and that there are not buttons to accept or cancel.

• When does this issue occur?
  It occurs only if you have not previously selected the other option (original format). To replicate the problem in that case clear the cookies for the site, restart the browser and try again.

• Which page(s) does it occurs on?
  Dataset details page

• What happens?
  See steps to reproduce above.

• To whom does it occur (all users, curators, superusers)?
  All users.

• What did you expect to happen?
  The same pop-up that appears in the "original format" option.

Which version of Dataverse are you using?
6.9

Any related open or closed issues to this bug report?
No

Are you thinking about creating a pull request for this issue?
Yes.