firebase challenge!!! looks like theres a write call to the database in the network requests. quick look at the javascript confirms this. the offending function sendTHEPIXEL():
We're no strangers to love
You know the rules and so do ...
Never gonna tell a lie and hurt you
Never gonna give you up
Never gonna let you down
Never gonna run around and desert you
Never gonna make you cry
Never gonna say goodbye
Never gonna tell a lie and hurt you"