Issue 1:
Electron version: 1.4.3

Operating system: macOS Sierra 10.12 (16A323)

Here is my code for electron/main.js:

mainWindow.webContents.on('new-window', function(e, url) {
e.preventDefault();
electron.shell.openExternal(url);
});

Links open correctly in default external browser (Google Chrome), but after a few seconds the app crashes with:

Process: myapp [70908]
Path: /Users/USER/*/myapp.app/Contents/MacOS/myapp
Identifier: com.electron.myapp
Version: 1.1.1 (1.1.1)
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: myapp [70908]
User ID: 501

Date/Time: 2016-10-13 11:57:26.037 +0200
OS Version: Mac OS X 10.12 (16A323)
Report Version: 12
Anonymous UUID: 57923C28-422F-B3A3-5970-894117C0542F

Sleep/Wake UUID: E1BCC90D-1FB3-4DEF-A401-2DDFCA8D62C7

Time Awake Since Boot: 52000 seconds
Time Since Wake: 10000 seconds

System Integrity Protection: enabled

Crashed Thread: 0 CrBrowserMain Dispatch queue: com.apple.main-thread

Exception Type: EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x0000000000000002, 0x0000000000000000
Exception Note: EXC_CORPSE_NOTIFY

Termination Signal: Trace/BPT trap: 5
Termination Reason: Namespace SIGNAL, Code 0x5
Terminating Process: exc handler [0]

Thread 0 Crashed:: CrBrowserMain Dispatch queue: com.apple.main-thread
0 com.github.electron.framework 0x0000000109d086e1 0x109b27000 + 1971937
1 com.github.electron.framework 0x0000000109d2109f 0x109b27000 + 2072735
2 com.github.electron.framework 0x0000000109c7e455 mate::WrappableBase::GetWrapper() + 101
3 com.github.electron.framework 0x0000000109b900c9 mate::EventEmitter<atom::api::WebContents>::GetWrapper() + 9
4 com.github.electron.framework 0x0000000109b92ef9 bool mate::EventEmitter<atom::api::WebContents>::EmitWithSender<int>(base::BasicStringPiece<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, content::WebContents*, IPC::Message*, int const&) + 89
5 com.github.electron.framework 0x0000000109b89823 bool mate::EventEmitter<atom::api::WebContents>::Emit<int>(base::BasicStringPiece<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > > const&, int const&) + 19
6 com.github.electron.framework 0x0000000109b89801 atom::api::WebContents::RenderViewDeleted(content::RenderViewHost*) + 81
7 com.github.electron.framework 0x0000000109b88537 atom::api::WebContents::~WebContents() + 199
8 com.github.electron.framework 0x0000000109b88629 atom::api::WebContents::~WebContents() + 9
9 com.github.electron.framework 0x0000000109b886be atom::api::WebContents::~WebContents() + 14
10 com.github.electron.framework 0x0000000109b886dd non-virtual thunk to atom::api::WebContents::~WebContents() + 13
11 com.github.electron.framework 0x0000000109c7e6e3 mate::WrappableBase::SecondWeakCallback(v8::WeakCallbackInfo<mate::WrappableBase> const&) + 19
12 libnode.dylib 0x000000010de3f396 v8::internal::GlobalHandles::DispatchPendingPhantomCallbacks(bool) + 854
13 libnode.dylib 0x000000010de3f42e v8::internal::GlobalHandles::PostGarbageCollectionProcessing(v8::internal::GarbageCollector, v8::GCCallbackFlags) + 46
14 libnode.dylib 0x000000010de4e8f8 v8::internal::Heap::PerformGarbageCollection(v8::internal::GarbageCollector, v8::GCCallbackFlags) + 1768
15 libnode.dylib 0x000000010de4dd44 v8::internal::Heap::CollectGarbage(v8::internal::GarbageCollector, char const*, char const*, v8::GCCallbackFlags) + 676
16 libnode.dylib 0x000000010de4da48 v8::internal::Heap::CollectAllAvailableGarbage(char const*) + 104
17 libnode.dylib 0x000000010dae3914 v8::Isolate::LowMemoryNotification() + 196
18 com.github.electron.framework 0x0000000109bbfce0 void base::internal::RunnableAdapter<void (v8::Isolate::*)()>::Run<v8::Isolate*>(v8::Isolate*&&) const + 32
19 com.github.electron.framework 0x0000000109bbfca9 void base::internal::InvokeHelper<false, void>::MakeItSo<base::internal::RunnableAdapter<void (v8::Isolate::*)()> const&, v8::Isolate*>(base::internal::RunnableAdapter<void (v8::Isolate::*)()> const&&&, v8::Isolate*&&) + 9
20 com.github.electron.framework 0x0000000109bbfc91 void base::internal::Invoker<base::internal::BindState<base::internal::RunnableAdapter<void (v8::Isolate::*)()>, base::internal::UnretainedWrapper<v8::Isolate> >, void ()>::RunImpl<base::internal::RunnableAdapter<void (v8::Isolate::*)()> const&, std::__1::tuple<base::internal::UnretainedWrapper<v8::Isolate> > const&, 0ul>(base::internal::RunnableAdapter<void (v8::Isolate::*)()> const&&&, std::__1::tuple<base::internal::UnretainedWrapper<v8::Isolate> > const&&&, base::IndexSequence<0ul>) + 33
21 com.github.electron.framework 0x0000000109bbfbb4 base::internal::Invoker<base::internal::BindState<base::internal::RunnableAdapter<void (v8::Isolate::*)()>, base::internal::UnretainedWrapper<v8::Isolate> >, void ()>::Run(base::internal::BindStateBase*) + 20
22 com.github.electron.framework 0x0000000109d63769 0x109b27000 + 2344809
23 com.github.electron.framework 0x0000000109d097fb 0x109b27000 + 1976315
24 com.github.electron.framework 0x0000000109d2a4dc 0x109b27000 + 2110684
25 com.github.electron.framework 0x0000000109d2a7ec 0x109b27000 + 2111468
26 com.github.electron.framework 0x0000000109d2adcb 0x109b27000 + 2112971
27 com.github.electron.framework 0x0000000109cff189 0x109b27000 + 1933705
28 com.github.electron.framework 0x0000000109d2156a 0x109b27000 + 2073962
29 com.github.electron.framework 0x0000000109cfeb74 0x109b27000 + 1932148
30 com.apple.CoreFoundation 0x00007fffa9cdf581 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
31 com.apple.CoreFoundation 0x00007fffa9cc098c __CFRunLoopDoSources0 + 556
32 com.apple.CoreFoundation 0x00007fffa9cbfe76 __CFRunLoopRun + 934
33 com.apple.CoreFoundation 0x00007fffa9cbf874 CFRunLoopRunSpecific + 420
34 com.apple.HIToolbox 0x00007fffa925ff6c RunCurrentEventLoopInMode + 240
35 com.apple.HIToolbox 0x00007fffa925fda1 ReceiveNextEventCommon + 432
36 com.apple.HIToolbox 0x00007fffa925fbd6 _BlockUntilNextEventMatchingListInModeWithFilter + 71
37 com.apple.AppKit 0x00007fffa79565f5 _DPSNextEvent + 1093
38 com.apple.AppKit 0x00007fffa80668eb -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 1637
39 com.apple.AppKit 0x00007fffa794afbd -[NSApplication run] + 926
40 com.github.electron.framework 0x0000000109cff9be 0x109b27000 + 1935806
41 com.github.electron.framework 0x0000000109cfefc4 0x109b27000 + 1933252
42 com.github.electron.framework 0x0000000109d40821 0x109b27000 + 2201633
43 com.github.electron.framework 0x000000010a45da2b 0x109b27000 + 9660971
44 com.github.electron.framework 0x000000010a45d880 0x109b27000 + 9660544
45 com.github.electron.framework 0x000000010a45fd82 0x109b27000 + 9670018
46 com.github.electron.framework 0x000000010a459dcd 0x109b27000 + 9645517
47 com.github.electron.framework 0x000000010a3c55c0 0x109b27000 + 9037248
48 com.github.electron.framework 0x000000010a3c47a6 0x109b27000 + 9033638
49 com.github.electron.framework 0x0000000109b28b47 AtomMain + 71
50 com.electron.myapp 0x0000000109b20f26 main + 38
51 libdyld.dylib 0x00007fffbed91255 start + 1

...

Logical CPU: 2
Error Code: 0x00000000
Trap Number: 3

...

Model: MacBookAir4,2, BootROM MBA41.0077.B14, 2 processors, Intel Core i5, 1,7 GHz, 4 GB, SMC 1.73f66
Graphics: Intel HD Graphics 3000, Intel HD Graphics 3000, Built-In
Memory Module: BANK 0/DIMM0, 2 GB, DDR3, 1333 MHz, 0x80CE, 0x4D34373142353737334448302D4348392020
Memory Module: BANK 1/DIMM0, 2 GB, DDR3, 1333 MHz, 0x80CE, 0x4D34373142353737334448302D4348392020
AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0xE9), Broadcom BCM43xx 1.0 (5.106.98.100.24)
Bluetooth: Version 5.0.0f18, 3 services, 27 devices, 1 incoming serial ports
Network Service: USB 10/100/1000 LAN, Ethernet, en3
Network Service: Wi-Fi, AirPort, en0
Serial ATA Device: APPLE SSD SM256C, 251 GB
USB Device: USB 2.0 Bus
USB Device: FaceTime Camera (Built-in)
USB Device: Hub
USB Device: Hub
USB Device: Quickfire Rapid i
USB Device: ROCCAT Lua
USB Device: Apple Internal Keyboard / Trackpad
USB Device: BRCM20702 Hub
USB Device: Bluetooth USB Host Controller
USB Device: USB 2.0 Bus
USB Device: Hub
USB Device: USB2.0 Hub
USB Device: USB 10/100/1000 LAN
USB Device: Card Reader
Thunderbolt Bus: MacBook Air, Apple Inc., 8.1

Issue 2:
Electron version: 1.4.2

Operating system: macOS 10.12

STEPS:

Run in shell: ~/Downloads/electron-v1.4.2-darwin-x64/Elec ron.app/Contents/MacOS/Electron .

Click click me in the window.

Wait for 30-70 seconds for the app to crash.

index.js

const { BrowserWindow, app } = require('electron');
let win;
app.on('ready', () => {
win = new BrowserWindow({ webPreferences: { sandbox: true } })
win.loadURL(`file://${__dirname}/index.html`)
win.webContents.on('new-window', (e, url) => e.preventDefault())
}

index.html

<!DOCTYPE html>
click here
<script>
document.onclick = () => window.open('second.html', '_blank', 'width=800,height=200,location=0,scrollbars=0,status=0')
</script>

Console text when crashed

[24501:1004/173223:FATAL:wrappable.cc(24)] Check failed: !wrapper_.IsEmpty().
0 Electron Framework 0x0000000109b11cc3 _ZN4base8internal14NarrowingRangeIilE3minEv + 434723
1 Electron Framework 0x0000000109b29577 _ZN4base8internal14NarrowingRangeIilE3minEv + 531159
2 Electron Framework 0x0000000109a790f5 _ZN4mate13WrappableBase10GetWrapperEv + 101
3 Electron Framework 0x000000010998a2b9 _ZN4mate12EventEmitterIN4atom3api11WebContentsEE10GetWrapperEv + 9
4 Electron Framework 0x000000010998d009 _ZN4mate12EventEmitterIN4atom3api11WebContentsEE14EmitWithSenderIJiEEEbRKN4base16BasicStringPieceINSt3__112basic_stringIcNS8_11char_traitsIcEENS8_9allocatorIcEEEEEEPN7content11WebContentsEPN3IPC7MessageEDpRKT_ + 89
5 Electron Framework 0x0000000109983a13 _ZN4mate12EventEmitterIN4atom3api11WebContentsEE4EmitIJiEEEbRKN4base16BasicStringPieceINSt3__112basic_stringIcNS8_11char_traitsIcEENS8_9allocatorIcEEEEEEDpRKT_ + 19
6 Electron Framework 0x00000001099839f1 _ZN4atom3api11WebContents17RenderViewDeletedEPN7content14RenderViewHostE + 81
7 Electron Framework 0x0000000109982727 _ZN4atom3api11WebContentsD2Ev + 199
8 Electron Framework 0x0000000109982819 _ZN4atom3api11WebContentsD1Ev + 9
9 Electron Framework 0x00000001099828ae _ZN4atom3api11WebContentsD0Ev + 14
10 Electron Framework 0x00000001099828cd _ZThn48_N4atom3api11WebContentsD0Ev + 13
11 Electron Framework 0x0000000109a79383 _ZN4mate13WrappableBase18SecondWeakCallbackERKN2v816WeakCallbackInfoIS0_EE + 19
12 libnode.dylib 0x000000010dd8c396 _ZN2v88internal13GlobalHandles31DispatchPendingPhantomCallbacksEb + 854
13 libnode.dylib 0x000000010dd8c42e _ZN2v88internal13GlobalHandles31PostGarbageCollectionProcessingENS0_16GarbageCollectorENS_15GCCallbackFlagsE + 46
14 libnode.dylib 0x000000010dd9b8f8 _ZN2v88internal4Heap24PerformGarbageCollectionENS0_16GarbageCollectorENS_15GCCallbackFlagsE + 1768
15 libnode.dylib 0x000000010dd9ad44 _ZN2v88internal4Heap14CollectGarbageENS0_16GarbageCollectorEPKcS4_NS_15GCCallbackFlagsE + 676
16 libnode.dylib 0x000000010dd9aa48 _ZN2v88internal4Heap26CollectAllAvailableGarbageEPKc + 104
17 libnode.dylib 0x000000010da30914 _ZN2v87Isolate21LowMemoryNotificationEv + 196
18 Electron Framework 0x00000001099ba430 _ZNK4base8internal15RunnableAdapterIMN2v87IsolateEFvvEE3RunIPS3_JEEEvOT_DpOT0_ + 32
19 Electron Framework 0x00000001099ba3f9 _ZN4base8internal12InvokeHelperILb0EvE8MakeItSoIRKNS0_15RunnableAdapterIMN2v87IsolateEFvvEEEJPS6_EEEvOT_DpOT0_ + 9
20 Electron Framework 0x00000001099ba3e1 _ZN4base8internal7InvokerINS0_9BindStateINS0_15RunnableAdapterIMN2v87IsolateEFvvEEEJNS0_17UnretainedWrapperIS5_EEEEEFvvEE7RunImplIRKS8_RKNSt3__15tupleIJSA_EEEJLm0EEEEvOT_OT0_NS_13IndexSequenceIJXspT1_EEEE + 33
21 Electron Framework 0x00000001099ba304 _ZN4base8internal7InvokerINS0_9BindStateINS0_15RunnableAdapterIMN2v87IsolateEFvvEEEJNS0_17UnretainedWrapperIS5_EEEEEFvvEE3RunEPNS0_13BindStateBaseE + 20
22 Electron Framework 0x0000000109b6c269 _ZN4base8internal14NarrowingRangeIilE3minEv + 804809
23 Electron Framework 0x0000000109b121bb _ZN4base8internal14NarrowingRangeIilE3minEv + 435995
24 Electron Framework 0x0000000109b32f8c _ZN4base8internal14NarrowingRangeIilE3minEv + 570604
25 Electron Framework 0x0000000109b3329c _ZN4base8internal14NarrowingRangeIilE3minEv + 571388
26 Electron Framework 0x0000000109b3387b _ZN4base8internal14NarrowingRangeIilE3minEv + 572891
27 Electron Framework 0x0000000109b07b49 _ZN4base8internal14NarrowingRangeIilE3minEv + 393385
28 Electron Framework 0x0000000109b29f4a _ZN4base8internal14NarrowingRangeIilE3minEv + 533674
29 Electron Framework 0x0000000109b07534 _ZN4base8internal14NarrowingRangeIilE3minEv + 391828
30 CoreFoundation 0x00007fff832e6551 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
31 CoreFoundation 0x00007fff832c76bd __CFRunLoopDoSources0 + 557
32 CoreFoundation 0x00007fff832c6bb6 __CFRunLoopRun + 934
33 CoreFoundation 0x00007fff832c65b4 CFRunLoopRunSpecific + 420
34 HIToolbox 0x00007fff82867f6c RunCurrentEventLoopInMode + 240
35 HIToolbox 0x00007fff82867da1 ReceiveNextEventCommon + 432
36 HIToolbox 0x00007fff82867bd6 _BlockUntilNextEventMatchingListInModeWithFilter + 71
37 AppKit 0x00007fff80f5e5f5 _DPSNextEvent + 1093
38 AppKit 0x00007fff8166e8eb -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 1637
39 AppKit 0x00007fff80f52fbd -[NSApplication run] + 926
40 Electron Framework 0x0000000109b0837e _ZN4base8internal14NarrowingRangeIilE3minEv + 395486
41 Electron Framework 0x0000000109b07984 _ZN4base8internal14NarrowingRangeIilE3minEv + 392932
42 Electron Framework 0x0000000109b492d1 _ZN4base8internal14NarrowingRangeIilE3minEv + 661553
43 Electron Framework 0x000000010a268f6b _ZN4base8internal14NarrowingRangeIilE3minEv + 8131787
44 Electron Framework 0x000000010a268dc0 _ZN4base8internal14NarrowingRangeIilE3minEv + 8131360
45 Electron Framework 0x000000010a26b2c2 _ZN4base8internal14NarrowingRangeIilE3minEv + 8140834
46 Electron Framework 0x000000010a26530d _ZN4base8internal14NarrowingRangeIilE3minEv + 8116333
47 Electron Framework 0x000000010a1ce100 _ZN4base8internal14NarrowingRangeIilE3minEv + 7497312
48 Electron Framework 0x000000010a1cd2e6 _ZN4base8internal14NarrowingRangeIilE3minEv + 7493702
49 Electron Framework 0x0000000109922d47 AtomMain + 71
50 Electron 0x000000010991cf26 main + 38
51 libdyld.dylib 0x00007fff98306255 start + 1
52 ??? 0x0000000000000002 0x0 + 2

Trace/BPT trap: 5