Due to some reasons that we all know about, Sci-Hub often changes its domain name to other TLDs. The
.mn site on Papers, for example, is no longer available. To solve this problem I've just created Template:Sci-Hub so we can just keep the knowledge of the sci-hub web address in the same place. Maybe try using it on the Papers page?
P.S. You don't have to modify the domain name to get to Sci-Hub! Just add a https://sci-hub.tw/ prefix: https://www.nature.com/articles/nbt0308-274 becomes https://sci-hub.tw/https://www.nature.com/articles/nbt0308-274.
P.P.S. Is the spiro/licorice regimen on the template page good enough for putting into Papers? I picked it up from the Wikipedia page for spiro, and the side effect reduction sure looks promising...