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**Do you want to request a *feature* or report a *bug*?**
Bug

**What is the current behavior?**
The profiler tab only shows this message even though I have a version greater than 16.5.

![Screen Shot 2019-09-06 at 13 26 47](https://user-images.githubusercontent.com/5483459/64444238-0d706c00-d0aa-11e9-8d32-810465a13433.png)


Something strange on the console is this message and just appears when the extension is active.

![Screen Shot 2019-09-06 at 13 25 17](https://user-images.githubusercontent.com/5483459/64444170-e74acc00-d0a9-11e9-8b7c-acaa31e50cea.png)

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
React **16.9.0**
React DevTools **4.0.6-a39d9c3**

const stringTableSize = operations[i++];
  const stringTableEnd = i + stringTableSize;
  while (i < stringTableEnd) {
    const nextLength = operations[i++];
    const nextString = utfDecodeString(
      (operations.slice(i, i + nextLength): any),
    );
    stringTable.push(nextString);
    i += nextLength;
  }
  while (i < operations.length) {
    const operation = operations[i];
    switch (operation) {
      case TREE_OPERATION_ADD: {
        const id = ((operations[i + 1]: any): number);
        const type = ((operations[i + 2]: any): ElementType);
        i += 3;
        if (type === ElementTypeRoot) {
          logs.push(`Add new root node ${id}`);
          i++; 
          i++; 
        } else {
          const parentID = ((operations[i]: any): number);
          i++;
          i++; 
          const displayNameStringID = operations[i];
          const displayName = stringTable[displayNameStringID];
          i++;
          i++; 
          logs.push(