Crash: WebSocket.swift line 241 FoundationStream.write(data:)

[colin1994]

I've recently started seeing this crash in Crashlytics (generated from an app that users have downloaded from the App Store).

Unfortunately, I don't know more information than the crash info below so I cannot recreate the cause.

Crashed: NSOperationQueue 0x15130d400 (QOS: UNSPECIFIED)
EXC_BAD_ACCESS KERN_INVALID_ADDRESS 0x0000000adc3d4640

0  libobjc.A.dylib                0x1bfaf0fb0 objc_msgSend + 16
1  WebSocket                    0x105f5784c FoundationStream.write(data:) + 241 (WebSocket.swift:241)
2  WebSocket                    0x105f586ec protocol witness for WSStream.write(data:) in conformance FoundationStream + 20 (<compiler-generated>:20)
3  WebSocket                    0x105f5f650 closure #1 in WebSocket.dequeueWrite(_:code:writeCompletion:) + 1268 (WebSocket.swift:1268)
4  WebSocket                    0x105adcb8c thunk for @escaping @callee_guaranteed () -> () + 28 (<compiler-generated>:28)
5  Foundation                     0x1c01ac9d4 <redacted> + 24
6  Foundation                     0x1c00ae4a8 <redacted> + 104
7  Foundation                     0x1c01aed30 <redacted> + 24
8  Foundation                     0x1c00ae124 <redacted> + 740
9  Foundation                     0x1c01af75c <redacted> + 24
10 Foundation                     0x1c01af21c <redacted> + 184
11 libdispatch.dylib              0x1bfa8e39c <redacted> + 144
12 libdispatch.dylib              0x1bfa81fd8 <redacted> + 20
13 libdispatch.dylib              0x1bfa84758 <redacted> + 408
14 libdispatch.dylib              0x1bfa83f74 <redacted> + 784
15 libdispatch.dylib              0x1bfa90bd4 <redacted> + 348
16 libdispatch.dylib              0x1bfa91384 <redacted> + 120
17 libsystem_pthread.dylib        0x1bfae7690 _pthread_wqthread + 216
18 libsystem_pthread.dylib        0x1bfaed9e8 start_wqthread + 8

Environment: Birdsong, 0.6

Can you help to see this? @sjrmanning