Greetings Jan,
Our developers have confirmed ScienceDirect has implemented a change to URL redirecting, which now employs JavaScript - EndNote’s Find Full Text functionality cannot query full text resources that utilize JavaScript due to security concerns. A product enhancement request has been submitted to Development, but unless ScienceDirect reverses their decision to use JavaScript, there’s no possible workaround to restore Find Full Text search access to ScienceDirect without re-engineering how our Find Full Text feature functions. I do apologize for any inconvenience caused by this situation.