cutting off front and back frames with agg

[PlasmaHH]

Hi,

I tried the asciinema -> agg workflow and what I noticed is that often a bit of the setup at the start is unimportant for the final gif as well as the end. So it would be really helpful I guess if agg had simple options to drop frames front and back to trim it to the final one.

[ku1ik]

That makes sense, sounds like a useful feature 👍