iOS - Webthread - Javascript Core crash

I’m getting a strange crash in the web thread, happening when that I don’t know. so what could be the cause of this problem?

Here’s the crash log for reference:

Device : iPhone 6s
IOS Version : 12.1.2 (16C101)

Implemented Fabric Crashlytics Plugin :

0 JavaScriptCore 0x1a43f1518 bmalloc::Heap::allocateLarge(std::__1::unique_lockbmalloc::Mutex&, unsigned long, unsigned long) + 24
1 JavaScriptCore 0x1a43f150c bmalloc::Heap::allocateLarge(std::__1::unique_lockbmalloc::Mutex&, unsigned long, unsigned long) + 12
2 JavaScriptCore 0x1a43ebe10 bmalloc::Allocator::allocateLarge(unsigned long) + 152
3 JavaScriptCore 0x1a43ebc04 bmalloc::Allocator::reallocate(void*, unsigned long) + 512
4 JavaScriptCore 0x1a43b5e78 WTF::fastRealloc(void*, unsigned long) + 52
5 JavaScriptCore 0x1a43cfac4 + 84
6 JavaScriptCore 0x1a43ce2e8 + 104
7 JavaScriptCore 0x1a43cf1e8 WTF::StringBuilder::appendQuotedJSONString(WTF::String const&) + 452
8 JavaScriptCore 0x1a4ce60ac JSC::Stringifier::appendStringifiedValue(WTF::StringBuilder&, JSC::JSValue, JSC::Stringifier::Holder const&, JSC::PropertyNameForFunctionCall const&) + 1232
9 JavaScriptCore 0x1a4ce7bb4 JSC::Stringifier::Holder::appendNextProperty(JSC::Stringifier&, WTF::StringBuilder&) + 2764
10 JavaScriptCore 0x1a4ce66bc JSC::Stringifier::appendStringifiedValue(WTF::StringBuilder&, JSC::JSValue, JSC::Stringifier::Holder const&, JSC::PropertyNameForFunctionCall const&) + 2784
11 JavaScriptCore 0x1a4ce59e0 JSC::Stringifier::stringify(JSC::JSValue) + 348
12 JavaScriptCore 0x1a4cecc88 JSC::JSONProtoFuncStringify(JSC::ExecState*) + 208
13 JavaScriptCore 0x1a4400814 llint_entry + 32692
14 JavaScriptCore 0x1a43ffd34 llint_entry + 29908
15 JavaScriptCore 0x1a4400200 llint_entry + 31136
16 JavaScriptCore 0x1a43ffd34 llint_entry + 29908
17 JavaScriptCore 0x1a43ffd34 llint_entry + 29908
18 JavaScriptCore 0x1a43ffd34 llint_entry + 29908
19 JavaScriptCore 0x1a43ffd9c llint_entry + 30012
20 JavaScriptCore 0x1a43ffd34 llint_entry + 29908
21 JavaScriptCore 0x1a43ffd34 llint_entry + 29908
22 JavaScriptCore 0x1a43f8664 vmEntryToJavaScript + 308
23 JavaScriptCore 0x1a4a67840 JSC::Interpreter::executeCall(JSC::ExecState*, JSC::JSObject*, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&) + 424
24 JavaScriptCore 0x1a4c1ee94 JSC::profiledCall(JSC::ExecState*, JSC::ProfilingReason, JSC::JSValue, JSC::CallType, JSC::CallData const&, JSC::JSValue, JSC::ArgList const&, WTF::NakedPtrJSC::Exception&) + 200
25 WebCore 0x1a6409458 WebCore::JSEventListener::handleEvent(WebCore::ScriptExecutionContext&, WebCore::Event&) + 1100
26 WebCore 0x1a66748f4 WebCore::EventTarget::fireEventListeners(WebCore::Event&, WTF::Vector<WTF::RefPtr<WebCore::RegisteredEventListener, WTF::DumbPtrTraitsWebCore::RegisteredEventListener >, 1ul, WTF::CrashOnOverflow, 16ul>) + 736
27 WebCore 0x1a6672214 WebCore::EventTarget::fireEventListeners(WebCore::Event&) + 260
28 WebCore 0x1a66745f8 WebCore::EventTarget::dispatchEvent(WebCore::Event&) + 124
29 WebCore 0x1a6a6391c WebCore::DOMWindow::postMessageTimerFired(WebCore::PostMessageTimer&) + 164
30 WebCore 0x1a6a6b224 WebCore::PostMessageTimer::fired() + 108
31 WebCore 0x1a6b4402c WebCore::ThreadTimers::sharedTimerFiredInternal() + 352
32 WebCore 0x1a6b88a54 WebCore::timerFired(__CFRunLoopTimer*, void*) + 28
33 CoreFoundation 0x19d041828 CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION + 28
34 CoreFoundation 0x19d041558 __CFRunLoopDoTimer + 864
35 CoreFoundation 0x19d040d8c __CFRunLoopDoTimers + 248
36 CoreFoundation 0x19d03bc68 __CFRunLoopRun + 1880
37 CoreFoundation 0x19d03b1f0 CFRunLoopRunSpecific + 436
38 WebCore 0x1a5eaaeec RunWebThread(void*) + 592
39 libsystem_pthread.dylib 0x19cccc25c _pthread_body + 128
40 libsystem_pthread.dylib 0x19cccc1bc _pthread_start + 48
41 libsystem_pthread.dylib 0x19cccfcf4 thread_start + 4