### Website or app

https://codesandbox.io/s/react-playground-forked-j4niq

### Repro steps

Emoji seem supported but produce strange symbole

![image](https://user-images.githubusercontent.com/24865815/133793744-55a55582-90ad-425f-8a40-4c061a3c1d80.png)

To test emoji on Window Os, use `[win]+[.]` 🟩


### How often does this bug happen?

Every time

### DevTools package (automated)

_No response_

### DevTools version (automated)

_No response_

### Error message (automated)

_No response_

### Error call stack (automated)

_No response_

### Error component stack (automated)

_No response_

### GitHub query string (automated)

_No response_
i++;
      }
    }
     F
    for (let j = 0; j < pendingOperations.length; j++) {
      operations[i + j] = pendingOperations[j];
    }
    i += pendingOperations.length;
     L
    flushOrQueueOperations(operations);
     R
    pendingOperations.length = 0;
    pendingRealUnmountedIDs.length = 0;
    pendingSimulatedUnmountedIDs.length = 0;
    pendingUnmountedRootID = null;
    pendingStringTable.clear();
    pendingStringTableLength = 0;
  }
  function getStringID(str: string | null): number {
    if (str === null) {
      return 0;
    }
    const existingID = pendingStringTable.get(str);
    if (existingID !== undefined) {
      return existingID;
    }
    const stringID = pendingStringTable.size + 1;
    pendingStringTable.set(str, stringID);
     T
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