firebase-ios-sdk: Crashed at FIRComponentContainer on 6.7.0

[REQUIRED] Step 2: Describe your environment

• Firebase SDK version: 6.7.0
• Firebase Component: Below is from my Podfile.

    pod 'Firebase/Core', '~> 6.0'
    pod 'Firebase/AdMob'
    pod 'Firebase/Auth'
    pod 'Google-Mobile-Ads-SDK'
    pod 'Firebase/Messaging'
    pod 'Firebase/Functions'
    pod 'Firebase/RemoteConfig'
    pod 'Firebase/Performance'

[REQUIRED] Step 3: Describe the problem

Steps to reproduce:

Not sure how to reproduce so far, I just found some users of my app got this crash due to this issue. Seems it accesses non-existent key against cached instances. https://github.com/firebase/firebase-ios-sdk/blob/bb563c8497c0a8fb4d237604062535701dd7ba25/Firebase/Core/FIRComponentContainer.m#L150

Crashed: com.google.perf.FPREventsQueue
0  libobjc.A.dylib              0x223548d68 objc_msgSend + 8
1  CoreFoundation               0x22424bb60 -[__NSDictionaryM objectForKeyedSubscript:] + 212
2  MyApp                        0x104e26d78 -[FIRComponentContainer instanceForProtocol:] + 150 (FIRComponentContainer.m:150)
3  MyApp                        0x104e2710c +[FIRComponentType instanceForProtocol:inContainer:] + 25 (FIRComponentType.m:25)
4  MyApp                        0x104ef7eac -[FIRRemoteConfigComponent remoteConfigForNamespace:] + 4380917420
5  MyApp                        0x104ef4438 +[FIRRemoteConfig remoteConfigWithFIRNamespace:app:] + 4380902456
6  MyApp                        0x104e714c0 __38+[FPRRemoteConfigFlags sharedInstance]_block_invoke + 4380366016
7  ???                          0x223d9a484 (Missing)
8  ???                          0x223d6a234 (Missing)
9  MyApp                        0x104e71468 +[FPRRemoteConfigFlags sharedInstance] + 4380365928
10 MyApp                        0x104e702cc -[FPRConfigurations setupRemoteConfigFlags] + 4380361420
11 MyApp                        0x104e7020c -[FPRConfigurations update] + 4380361228
12 MyApp                        0x104e73500 __42-[FPRClient startWithConfiguration:error:]_block_invoke + 4380374272
(snip)

I’d like to help as much as possible if needed. Thanks!