Thunken recently released Permalink’s Awakening, a small open-source browser extension that adds a link to a page’s most durable URL next to its title.
Some publishers seem to go to great lengths to “hide” citation-friendly PIDs below the fold. This extension scans metadata to add, whenever possible, a clickable link to the page’s PID or most durable URL (DOI, PMID, arXiv ID, permalink, etc.) next to its title.
Permalink’s Awakening works on many journals and platforms, including but not limited to PubMed, arXiv, OJS, Wikipedia, Nature, Science, etc.
The extension can be installed from the Chrome Web Store: https://chrome.google.com/webstore/detail/permalinks-awakening/ciephhbpokgilmomciakhnglkmbpdoin. The code is available on GitHub: https://github.com/thunken/permalinks-awakening.