Where is stored youtube signature decoder?

[Dingo64]

From time to time Youtube changes their signature decoder and it's essential to download base.js and parse it. Where is the result of this parsing stored? Or is it downloading base.js everytime I run it?

Also how can I check if program needs updating?

[dstftw]

1. Stored in cache.
2. There is no such thing as "needs updating". If there is an update available you can update.