Trailhead - Live Agent File Upload bug - Help

Hey folks,

I'm completing my Live Agent Basics Trailhead (Get Started with Live Agent) and I'm testing my challenge here.

I follow instructions closely. I opened a case with "Refund Me" subject and Web source as asked.

As an agent, I request a file tranfer to attach to the case. Customer gets the request, uploads the file (I tried any size (up to 25 MB) and any format)). Customer immediately gets the following error "Your file upload failed..."

Agent on another hand is still thinking that the file is coming (has ability to cancel the transfer too).

Is this a bug??

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