Thread parsing possibly broken for A-List users

[lehrblogger]

A user reported to me that she was getting errors on every thread when running the script:

INFO: Fetching thread: https://www.okcupid.com/messages?readmsg=true&threadid=SOME_ID
ERROR: Fetch thread failed for URL: /messages?readmsg=true&threadid=SOME_ID with error 'NoneType' object has no attribute 'string'

The issue resolved itself a few days later, before we were able to figure out the root cause. The only thing that changed was that her A-List subscription had expired. Perhaps an A-List feature changes the message markup in a way that breaks the parsing?

Alternatively, it might have been a temporary issue with OkCupid blocking her IP (I'm not sure what error messages that would result in), or any number of other things. I don't have A-List right now so can't easily test the theory, but I wanted to document it in case others encounter the same issue.