Chrome plugin launchWebAuthFlow crashes with Pinterest - google-chrome

Question

I'm developing a Chrome extension that was reading some data (share numbers) from Pinterest. I had to stop development on it, but it was working OK (I was able to retrieve share numbers and all).
Now that my client wants this again, I restarted work but I'm really dumbfounded because the application now crashes Chrome when the launchWebAuthFlow method is called.
I am able to launch this kind of flow with Dropbox and other OAuth providers. For some reason, when using Pinterest the whole Chrome process crashes hard.
The auth code looks like this (*I've inlined some variables for readability):
var redirectUri = chrome.identity.getRedirectURL("pinterest");
var authUrl = 'https://api.pinterest.com/oauth/?' +
'response_type=code'+
'&redirect_uri='+ encodeURIComponent(redirectUri) +
'&client_id=4831470687770133014'+
'&scope=read_public'+
'&state=somethingRandom';
chrome.identity.launchWebAuthFlow(
{'url': authUrl, 'interactive': true},
function(redirect_url) { console.log(redirect_url);}
);
The authUrl then looks something like this:
https://api.pinterest.com/oauth/?response_type=code&redirect_uri=https://bkjcojjjcgnfgncncmdlbeemoljomghm.chromiumapp.org/pinterest&client_id=4831470687770133014&scope=read_public&state=3875186
If you copy/paste this URL in your browser, you'll see that it works. But when used part of the launchWebAuthFlow, BOOM!
Why??
Spec:
Chrome: 53.0.2785.143
Mac OS: El Captain 10.11.6
This is the Mac OS crash report:
Process: Google Chrome [16077]
Path: /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
Identifier: com.google.Chrome
Version: 53.0.2785.143 (2785.143)
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: Google Chrome [16077]
User ID: 501
Date/Time: 2016-10-03 21:09:38.740 -0400
OS Version: Mac OS X 10.11.6 (15G31)
Report Version: 11
Anonymous UUID: AD141569-EBED-B1D4-DF7D-27A6CE685215
Sleep/Wake UUID: 8917F66A-5515-40E1-AA86-8BE0BE1DC1A9
Time Awake Since Boot: 14000 seconds
Time Since Wake: 1600 seconds
System Integrity Protection: enabled
Crashed Thread: 0 CrBrowserMain Dispatch queue: com.apple.main-thread
Exception Type: EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x00000000000001e8
VM Regions Near 0x1e8:
-->
__TEXT 00000001051ac000-00000001051ad000 [ 4K] r-x/rwx SM=COW /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
Thread 0 Crashed:: CrBrowserMain Dispatch queue: com.apple.main-thread
0 com.google.Chrome.framework 0x0000000109d656d2 0x105413000 + 76883666
1 com.google.Chrome.framework 0x0000000109d655c9 0x105413000 + 76883401
2 com.google.Chrome.framework 0x00000001055a42f6 0x105413000 + 1643254
3 com.google.Chrome.framework 0x00000001054c0201 0x105413000 + 709121
4 com.google.Chrome.framework 0x00000001054c03b7 0x105413000 + 709559
5 com.google.Chrome.framework 0x0000000106e3cc29 0x105413000 + 27434025
6 com.google.Chrome.framework 0x0000000106e467f7 0x105413000 + 27473911
7 com.google.Chrome.framework 0x000000010693a148 0x105413000 + 22180168
8 com.google.Chrome.framework 0x0000000106939889 0x105413000 + 22177929
9 com.google.Chrome.framework 0x0000000106e46ad7 0x105413000 + 27474647
10 com.google.Chrome.framework 0x0000000106933a8e 0x105413000 + 22153870
11 com.google.Chrome.framework 0x00000001069315ea 0x105413000 + 22144490
12 com.google.Chrome.framework 0x00000001069318e4 0x105413000 + 22145252
13 com.google.Chrome.framework 0x000000010693ed33 0x105413000 + 22199603
14 com.google.Chrome.framework 0x00000001059a201b 0x105413000 + 5828635
15 com.google.Chrome.framework 0x00000001059c47ac 0x105413000 + 5969836
16 com.google.Chrome.framework 0x00000001059c4abc 0x105413000 + 5970620
17 com.google.Chrome.framework 0x00000001059c4e1b 0x105413000 + 5971483
18 com.google.Chrome.framework 0x000000010599731d 0x105413000 + 5784349
19 com.google.Chrome.framework 0x00000001059ba71a 0x105413000 + 5928730
20 com.google.Chrome.framework 0x0000000105996d24 0x105413000 + 5782820
21 com.apple.CoreFoundation 0x00007fff98059881 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
22 com.apple.CoreFoundation 0x00007fff98038fbc __CFRunLoopDoSources0 + 556
23 com.apple.CoreFoundation 0x00007fff980384df __CFRunLoopRun + 927
24 com.apple.CoreFoundation 0x00007fff98037ed8 CFRunLoopRunSpecific + 296
25 com.apple.HIToolbox 0x00007fff909fb935 RunCurrentEventLoopInMode + 235
26 com.apple.HIToolbox 0x00007fff909fb76f ReceiveNextEventCommon + 432
27 com.apple.HIToolbox 0x00007fff909fb5af _BlockUntilNextEventMatchingListInModeWithFilter + 71
28 com.apple.AppKit 0x00007fff8f014df6 _DPSNextEvent + 1067
29 com.apple.AppKit 0x00007fff8f014226 -[NSApplication _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 454
30 com.apple.AppKit 0x00007fff8f008d80 -[NSApplication run] + 682
31 com.google.Chrome.framework 0x0000000105997b4e 0x105413000 + 5786446
32 com.google.Chrome.framework 0x0000000105997174 0x105413000 + 5783924
33 com.google.Chrome.framework 0x00000001059dc811 0x105413000 + 6068241
34 com.google.Chrome.framework 0x00000001054b6ce5 0x105413000 + 670949
35 com.google.Chrome.framework 0x0000000108efc984 0x105413000 + 61774212
36 com.google.Chrome.framework 0x0000000108efee02 0x105413000 + 61783554
37 com.google.Chrome.framework 0x0000000108ef8f2d 0x105413000 + 61759277
38 com.google.Chrome.framework 0x0000000105953c90 0x105413000 + 5508240
39 com.google.Chrome.framework 0x0000000105952ed6 0x105413000 + 5504726
40 com.google.Chrome.framework 0x0000000105415aea ChromeMain + 58
41 com.google.Chrome 0x00000001051acd42 main + 530
42 com.google.Chrome 0x00000001051acb24 0x1051ac000 + 2852
etc....

Answer 1

An update to Chrome about a month after this question was asked fixed this issue.