The easiest way to confirm there is an issue is to use the following link (no interaction required):
Opened with the developer tools / web inspector open, it loads correctly. If the developer tools are not open, it does not load.
It loads fine in Chrome, IE, Firefox
An interactive repro is also available (which actually outputs an error):
1. Close developer tools / web inspector window
2. Click “Kom igång!”
3. Check “Utbildningsnivå” in the left panel
4. Click “Klar” at the bottom
5. Click the leftmost layout button
6. Click “Linjediagram”
7. In the far right panel, click “Län”
8. Click all items in the “Län” list (crashes towards the end of the list: “undefined is not an object”)
Try again with developer tools open, at it does not crash.
Reproduced in Safari 9.1 (didn't try a nightly).
This bug appears to be fixed in trunk.
Can you re-test with a WebKit Nightly Build or Safari Technology Preview?
Yes. The problem is gone in Safari Technology Preview. Any hints for what goes wrong and any workarounds I can use to fix the issue in our app?
(In reply to comment #4)
> Yes. The problem is gone in Safari Technology Preview. Any hints for what
> goes wrong and any workarounds I can use to fix the issue in our app?
That's great news. Unfortunately, we don't have a clear diagnosis of the bug, so I don't have a workaround to recommend.