>>3
I must have missed that one. Which should I work on, an alternative /prog/ or a prog synch that will allow other users of the client side script to continue to post in deleted threads.

this looks like it could be promising

https://en.wikipedia.org/wiki/IndexedDB
http://www.w3.org/TR/IndexedDB/

Alternatively, it could be implemented in two components. One component would be the scraper and a server that listens only on localhost. Other applications can request threads from the localserver, or submit posts.

Then the /prog/ userscript will fetch content from the scraper server. When a post is made, the post goes to both the real /prog/ and the scraper server.