message: add vkui class at first render
diff: import React, { FC, useEffect, useRef, useState } from 'react';
  +import { canUseDOM } from '@vkontakte/vkjs/lib/dom';
  import { HasChildren } from 'types';
  import classNames from '../../lib/classNames';
  import { AppRootContext } from './AppRootContext';
  @@ -33,6 +34,10 @@ const AppRoot: FC<AppRootProps> = ({ children, embedded, window, sizeX, hasMouse
  const initialized = useRef(false);
  + if (canUseDOM && !initialized.current && !embedded) {
  + doc.classList.add('vkui');
  + }
  +
  // one time initialization and cleanup
  useIsomorphicLayoutEffect(() => {
  const parentNode = rootRef.current.parentElement;
  @@ -45,7 +50,6 @@ const AppRoot: FC<AppRootProps> = ({ children, embedded, window, sizeX, hasMouse
  setPortalRoot(portal);
  parentNode.classList.add('vkui__root', 'vkui__root--embedded');
  } else {
  - doc.classList.add('vkui');
  parentNode.classList.add('vkui__root');
  }
  initialized.current = true;
  