为什么overflow-x会更改overflow-y的行为？

Question

我正在yield call(delay, 1000 * SHOW_LOGIN_WALL_AFTER_IN_SECONDS); yield call(showModal); 容器上应用以下样式：

import { call, put, takeLatest } from 'redux-saga/effects';

export default function* showPermissionWall() {
  yield takeLatest(SHOW_TIMED_LOGIN_WALL, function* () {
    const { auth } = yield select(state => state);

    if (!auth.currentUser) {
      yield call(delay, 1000 * SHOW_LOGIN_WALL_AFTER_IN_SECONDS);
      yield call(showModal);
    }
  });
};

但是添加timeline也会向overflow-x: scroll; overflow-y: visible; 添加滚动。

overflow-x