You can take your laptop to a busy place, make a "free wifi" hotspot that runs everything through mitmproxy and you can steal everything.
I think "everything" is an overstatement. Browsers included the compromised intermediates in their CRLs within hours of disclosure.
So this isn't like Firesheep [0]. Yes, there would be vulnerable traffic, like the git client this thread is discusing, but it's not "everything"
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