Open Radar

 
Summary:
About 50% of the time when debugging JS in a WKWebView embedded in a native iOS application, the debugging session completely hangs. I am able to close the window and navigate between views (Debugging, Console, Timelines, etc) but I cannot inspect any variables, execute statements in the console, or resume the execution (Play/Pause execution, step into/over). Once this occurs I need to close the Safari window and re-attach. At times I need to completely restart the debugging session be re-launching my iOS app and then re-attaching with Safari.

Steps to Reproduce:
1. Run an iOS app containing a WKWebView 
2. Attach Safari to the WKWebView
3. Set a breakpoint on some javascript
4. Exercise javascript to hit the breakpoint
5. Wait a short while (10-20 seconds)
6. Attempt to step over the breakpoint line of code

Expected Results:
I can step over/into and resume javascript execution as needed.

Actual Results:
Sometimes the entire debugging session just becomes unresponsive. I can't step forward or resume javascript execution. 

Version:
iOS 8 and 9 (both on device and in the Simulator)
Safari 9.1.1 and Safari Technology Preview 9.1.2
OS X El Capitan 10.11.5

Notes:


Configuration:
I have not found a configuration where this _does not_ occurred.

Attachments: