As far as I can reconstruct, the user profile once had a votes tab, where anyone could see their own votes. That functionality was removed at some point, and is unlikely to return.
Nevertheless, I still would like to be able to see my own voting history, and perhaps even run some statistic evaluation on it.
Now since there is no support for this server-side, and since the data-dumps do not include voting information, the only way seems to be with some sort of client-side extension, like a userscript.
What would be a good approach to develop such an extension, and are there any good existing extensions for stackoverflow that one could use as a base? For example, which js-functions or http-requests would I have to catch to capture the casting of a vote.
Or is there already an extension that does this, which I have not found yet?