Created attachment 276409 [details] crash log To reproduce: 1. Launch Safari Technology Preview (I'm using Version 9.1.1 (11601.6.15, 11602.1.27)) 2. Go to https://github.com 3. Open the Web Inspector 4. Start record a timeline 5. Reload the page 6. Stop recording the timeline Somewhere in there the web process will crash. Sometimes it's immediately upon opening the Inspector, other times it's when clicking Record, or when finishing the recording. The stack trace always looks basically the same. See attached crash log.