[Video block] Showing the play button after inserting URL that doesn't exist

[RenanLukas]

Description

When inserting a URL that doesn't exist to the video block, the play button can still be tapped (but nothing loads, since the URL doesn't exist).

Step-by-step reproduction instructions

1 - Open a post or a page
2 - Add a video block
3 - Select the option "Insert from URL"
4 - Insert a URL that doesn't exist (e.g. https://www.thisisnotavalidurl.com.br) and tap "Apply"
5 - Observe the video block

Expected behaviour

The video block shows the "ADD VIDEO" button and doesn't load anything (this happens if I insert an invalid URL, such as "aaaaaaa").

Actual behaviour

The video block shows the play button and let's us play the video, even though it never loads since the URL doesn't exist.

Screenshots or screen recording (optional)

Uploading gutenberg_video_block.mov…

WordPress information

• WordPress version:
• Gutenberg version:
• Are all plugins except Gutenberg deactivated?
• Are you using a default theme (e.g. Twenty Twenty-One)?

Device information

• Device: iPhone SE
• Operating system: iOS 15.4
• WordPress app version: 20.3

[derekblank]

Confirmed as part of a few known issues related to displaying poster images and thumbnails within the video player. Also related:

• Videos added/edited on the web don't load in mobile editor wordpress-mobile/gutenberg-mobile#1152
• Video block: Video is not displayed when post is saved in the web version #30987
• Poster and Video being displayed at same time wordpress-mobile/gutenberg-mobile#965
• Video Block: add the ability to edit video thumbnail poster images wordpress-mobile/gutenberg-mobile#1493
• Saving a Video block with a file URL displays placeholder text in the editor #42515

[derekblank]

This issue is resolved via #49858.