iOS14 Switch Keyboard and reloadInputViews together lead to a never-ending loop

When we add observer for event UIKeyboardWillShowNotification,

and add reloadInputViews logic to the observer selector,
such as :
[self.inputFiled reloadInputViews];

then when user tap the earth icon to switch keyboard, it leads to a never-ending loop.

But it is totally fine on iOS 13 or below.

iOS14 Switch Keyboard and reloadInputViews together lead to a never-ending loop
 
 
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