This is a light weight tool built inside chrome, type

1
chrome://net-internals/#export

in the browser, you can find the following UI:

Now you can do whatever you can from the browser, this tool will capture all the packages, just like Wireshark.

Well I have to admit Wireshark if much more powerful for its awesome filter, but sometimes if you are really urgent and you just need a simple capture, this is a good option.

By the way, type chrome://chrome-urls/, you can find more interesting stuff :D