If you want something that does this across browsers without feeding details of what you're reading to Google, check out https://openaccessbutton.org/ or https://unpaywall.org/ (slightly different use cases)

Hmm, looks like none of the current #OAbutton or #unpaywall teams are here on fedi. Pinging @researchremix and @ethanwhite

@MartinVuilleme @jonny @BuluBane Do #Unpayall or #OAButton use the fatcat wiki? That’s all that https://scholar.archive.org does, in addition to hosting the PDFs as found when crawling the open web.