STEPS TO REPRODUCE: Using an engineering build, 1. navigate to webkit.org 2. open Inspector 3. turn on DebugUI (Cmd-Shift-Opt-D) 4. Right click, Protocol Debugging > Start 5. Switch to a Timelines or Network tab to collect new data 6. Right click, Protocol Debugging > Export... => The file contains no protocol trace information.
<rdar://problem/68666761>