Can't seek through video from Rails Active Storage with Rails-Webpacker React Frontend

Okay so I'm having an issue with seeking through videos in my react components with Rails Webpacker. I can make them play but I can't seek through them.

I'm using Rails Active Storage to upload the videos then sending their urls to my react component via an html attribute rendered by rails_blob_path(@post.video) (see below snippet on step 9). In my react component I have a <video /> element with the source being that parsed attribute. From there I have methods that control the element via a React.createRef(). One of the methods (play()) works as expected. However, my seek() method does not and I don't understand why.

I made a minified example (repo) to isolate the problem and here are the following steps I took:

1. rails new [app] --webpacker=react
2. cd into [app], rails active_storage:install
3. rails g scaffold post title:string
4. rails db:migrate
5. add line has_one_attached :video to app/models/post.rb
6. add :video to white-listed params in app/controllers/posts_controller.rb
7. add below snippet as a form field in app/views/posts/_form.html.erb

<div class="field">
  <%= form.label :video %>
  <%= form.file_field :video %>
</div>

9. add below to app/views/posts/show.html.erb

<div id='payload' url='<%= rails_blob_path(@post.video).to_json %>'></div>
<div id='hello-react'></div>
<%= javascript_pack_tag 'hello_react' %>

10. change app/javascript/packs/hello_react.jsx to have:

import React from 'react'
import ReactDOM from 'react-dom'

const node = document.getElementById('payload')
const url = JSON.parse(node.getAttribute('url'))

class App extends React.Component {

  componentWillMount() {
    this.videoRef = React.createRef()
  }

  seek = (seekTo = 0) => {
    this.videoRef.current.currentTime = seekTo
  }

  play = () => {
    this.videoRef.current.play()
  }

  render() {
    return (
      <div>
        <video ref={this.videoRef} controls>
          <source src={url} type='video/mp4' />
        </video>
        <button onClick={ (e) => {this.seek(5)} }>+5</button>
        <button onClick={ (e) => {this.play()} }>Play</button>
      </div>
    )
  }
}

ReactDOM.render(
  <App />,
  document.getElementById('hello-react')
)

11. start the server with rails s, go to localhost:3000/posts/new
12. create a post (you'll need a video to upload), you'll be redirected on submitting to the hello-react pack.

I've posted this before but have not gotten an answer. This is the first time I've made a separate project and outline of the steps to isolate the issue. Hopefully that relays how desperate I am. Please let me know if I need to explain any steps or if you all need anymore info. Thank you all in advance for your help.

Edit 11/11/18: One answer has pointed out that it is a browser issue. I was using Chrome for all my testing but when I used FireFox it worked as expected. Still not sure how to fix this so that the app works cross-browser.