Since Sci-Hub is not being updated with any new literature, [Nexus (STC)](https://www.reddit.com/r/scihub/comments/12detqs/standard_template_construct_store_and_search_the/)
is possibly the best option now. As an avid user of the browser extension
[Sci-Hub X Now!](https://github.com/gchenfc/sci-hub-now), I created the browser extension [Nexus Now!](https://github.com/aokellermann/nexus-now) that essentially has the same functionality, but redirects you
to the STC gateway for the given DOI.
You can install it here:
Mozilla add-on: https://addons.mozilla.org/en-US/firefox/addon/nexus-now/
Chrome extension: https://chrome.google.com/webstore/detail/nexus-now/neaelilefgejjfmjigboabajmmeonlfa
Edge add-on: https://microsoftedge.microsoft.com/addons/detail/nexus-now/jkjhclabmdjcghibkhpbbjoaijfpipkf
Bugs reports and pull requests are welcome here: https://github.com/aokellermann/nexus-now