Component used: Navigation
Version used: navigation-fragment-ktx, navigation-ui-ktx 2.6.0
Devices/Android versions reproduced on: All

If this is a bug in the library, we would appreciate if you could attach:
- Sample project to trigger the issue in the following github link: https://github.com/yotheone0909/NavigationDeeplinkDynamicBottomNav
When I open an app by the deep-link and back-pressing, it crashes. Also, bottom navigation tab 2 has dynamic fragment logic. It will change fragments when the API has a data response. (A sample project doesn't use the API.)

FATAL EXCEPTION: main
Process: com.example.navigationdeeplink, PID: 21948
java.lang.IllegalArgumentException: The fragment SecondFragment{389b31b} (e54e1f09-0f45-4e6c-a668-35e52c4c6ffc id=0x7f0800cc tag=cf5dd8f1-9576-4c91-975d-73e99d7e34b2) is unknown to the FragmentNavigator. Please use the navigate() function to add fragments to the FragmentNavigator managed FragmentManager.
at androidx.navigation.fragment.FragmentNavigator$onAttach$2.onBackStackChangeCommitted(FragmentNavigator.kt:143)
at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1918)
at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1845)
at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1782)
at androidx.fragment.app.FragmentManager$5.run(FragmentManager.java:565)
at android.os.Handler.handleCallback(Handler.java:942)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loopOnce(Looper.java:201)
at android.os.Looper.loop(Looper.java:288)
at android.app.ActivityThread.main(ActivityThread.java:7884)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

Issue does not occur when downgrade version 2.6.0 to 2.5.3 or normal open an app

Steps to reproduce
1. run script deeplink (file name test_deeplink.sh in a project)
2. press back system
3. App crashes with the above error