Keep source loaded after encoding

[Mine181]

(This has been posted in the discussions but no response has been given so I'm reposting it here) I like to tinker and adjust the encoding and do test encodes to see how it looks/how big the file is, Handbrake keeps the source loaded after encoding so you can adjust the parameters and test it again. Fastflix doesn't have this functionality and it gets very repetitive re-adding the same source just to adjust one minor thing.