Please test using both themes, Boost and Classic, and in more than one browser, and mention in a comment which browsers you've used.

The more supported browsers we can test with, the better, so anyone feel free to try this test even if you're not the assignee!

Requirements

• As admin, visit Site administration > Plugins > Text editors > Manage editors and make "Atto HTML editor" the default editor by moving it up to the first position.
• This test requires an image, an mp3 and an mp4 file with accompanying WebVTT files containing subtitles (such as the example files attached).
• VideoJS player should be enabled.

Testing

1. Log in as a user and go to a forum.
2. Click to add a new discussion and verify you see the Atto editor.
3. Click the Insert image icon.
4. Browse and upload an image from your computer.
5. Change the size to 400x400 and try to save it.
6. Verify you are warned you must either add a description or check the 'This image is decorative only' box.
7. Check the 'This image is decorative only' box and click Insert image.
8. Click Post to forum and verify that the image displays correctly.
9. Click to reply to your post.
10. Click the Insert Media icon.
11. Click the "Audio" tab
12. Browse and upload an mp3 file from your computer.
13. Click Insert media.
14. Click Post to forum and verify that the mp3 file displays correctly.
15. Edit the forum post, click the mp3 file, then the media button, and experiment with changing the advanced settings.
    Note: If you are not able to select the mp3 file by clicking, you might need to use the keyboard. In most browsers using Shift + Left/Right Arrow (same way as selecting text in the editor) works. Alternatively, dragging the mp3 file can work in some browsers.
16. Save changes and verify that the mp3 file displays as expected. 
17. Add another reply, this time using the Insert Media icon and clicking the "Video" tab
18. Browse and upload an mp4 file from your computer.
19. Click Post to forum and verify that the mp4 file displays correctly.
20. Edit the forum post, click the mp4 file, then the media button, and experiment with changing the display options.
21. Save changes and verify that the mp4 file displays as expected. 
22. Edit the forum post, click the mp4 file, then the media button, and experiment with changing the advanced settings.
23. Save changes and verify that the mp4 file displays as expected. 
24. Edit the forum post, click the mp4 file, then the media button, then add the WebVTT files.
25. Save changes and verify that subtitles are correctly displayed.