Fannish code
I made a browser extension for ao3 a little while back that highlights users listed as having blanket permission for podfics of their works in green. It sources this information from Rindle's fpslist and you can get it here: https://github.com/BrickGrass/Blanket-Permission-Highlighter.
I made another browser extension for ao3 that autofills a wordcount tag (eg: Wordcount: 5.000-10.000) whenever you open a bookmark creation or editing form. You can get it here: https://gist.github.com/BrickGrass/6ddece6536cb1b0558cf6f4d8eeb2ad9.
Another ao3 browser extension I have created permanently enables/disables a set of AO3 search filters. As in, every search you make can exclude works tagged with the warning underage, or you could always include works tagged as explicit and also exclude works tagged with major character death. You can get it here: https://gist.github.com/BrickGrass/505cbc1824bd6e98cbf2c52bb8cb4975.