Report: https://meta.wikimedia.org/wiki/Talk:The_Wikipedia_Library#Unable_to_validate_login_credentials

When I try to search the library, I get the error message:

We are unable to validate your login credentials. Please contact your institution for assistance. Please note, Referring URL authentication may have been prevented by antivirus or privacy control software. [Authentication Error Code 103]

at https://search-ebscohost-com.wikipedialibrary.idm.oclc.org/login.aspx?bquery=Foo&lang=en&custid=ns253359&groupid=main&profid=eds&scope=site&site=eds-live&direct=true&authtype=url

Highlighting text on page (say "Foo") and using a browser plugin that opens a tab with the URL https://wikipedialibrary.wmflabs.org/search/?q=Foo Manually opening a tab end entering the same URL gives an identical result.
However, if I use the method you describe, I am redirected to https://wikipedialibrary.wmflabs.org/users/my_library/ and if I search using the field there I get the same error, albeit at https://search-ebscohost-com.wikipedialibrary.idm.oclc.org/login.aspx?custid=ns253359&groupid=main&profid=eds&scope=site&site=eds-live&direct=true&authtype=url&lang=en-gb&bquery=Foo

neither whitelisting the sites nor disabling the add-ons makes any difference. I've also tried deleting cookies. I can search without issue in a different browser.

We've been unable to reproduce this issue, which seems to be related to referring URL data being blocked.