Those scripts may or may not be maintained.
Your userscripts plugin should update them automatically, if installed through their url.
Inject Obsidian Omnisearch results directly into your search engine. More information
Adds emojis to show most upvoted 🔥 and most commented 👄 links of Hacker News.
Enhance your reading experience of PCGamer articles. Removes the useless sidebar, interstitial unrelated videos, and Disqus comments.
Userscripts are kind of micro-addons for your browser. They're typically simple JavaScript files that are automatically executed on specific site, to alter their behavior or appearance.
They are managed with a "real" add-on, usually Greasemonkey or Tampermonkey.
More information here.