message: Fixed page refresh dev tool crash
diff: @@ -2,6 +2,7 @@ import React, {useState, useEffect} from 'react';
  import SnapshotsContainer from './SnapshotContainer';
  import VisualContainer from './VisualContainer';
  import {stateSnapshot, selectedTypes, stateSnapshotDiff} from '../../types';
  +import { render } from '@testing-library/react';
  interface MainContainerProps {
  // snapshotHistory is an array of stateSnapshots
  @@ -27,7 +28,9 @@ const MainContainer: React.FC<MainContainerProps> = ({
  // useEffect for renderIndex
  useEffect(() => {
  +
  setRenderIndex(snapshotHistory.length - 1);
  +
  }, [snapshotHistory]);
  // render containers passing necessary props
  @@ -49,7 +52,7 @@ const MainContainer: React.FC<MainContainerProps> = ({
  // snapshot at index [renderIndex -1]
  previousSnapshot={snapshotHistory[renderIndex - 1]}
  // snapshot at index [renderIndex]
  - currentSnapshot={snapshotHistory[renderIndex]}
  + currentSnapshot={(snapshotHistory[renderIndex]) ? snapshotHistory[renderIndex] : snapshotHistory[0]}
  // !passing through snapshotHistory
  snapshotHistory={snapshotHistory}
  // !passing through selections
  