Slow thumbnails loading time for videos in WP Media library

[develric]

This is a stub reminder issue to further investigate this comment noticed during internal call for testing (pbMoDN-1oy-p2v#comment-2755); better check if we download the full videos or if the thumbnails are very slowly generated on the server.

Expected behavior

When loading video thumbnails from WP Media library, they load in a timely way.

Actual behavior

When loading video thumbnails from WP Media library, they loads slow.

Steps to reproduce the behavior

• Be sure to have some videos (like 20) in the WP Media Library
• In GB add Video block
• Add video from WP Media Library
• Notice the video thumbnails load slow

Tested on [Pixel 3 Emu], Android [API 30], WPAndroid [#13216 CI Build]

[planarvoid]

I've checked the video media model objects and we don't have any other URL than the video URL. We're using Glide to show the thumbnail and it seems that this is the most efficient way to go at the moment. The perfect approach would be to generate the thumbnail when we're uploading the file.

[designsimply]

This came up in an App Review:

I've had the app for 2 weeks. In the beginning everything worked fine. For a few days now I have barely been able to edit posts. If I want to select videos from the media library, it does not work because it takes forever for the videos to build up and pictures are displayed in the video frame that do not belong to the video. When I then click one, the app usually hangs up. I've already checked everything. I think your app is overloaded!

^{3-star app review - Oct 26-2020 at 7:45 AM - Nokia 6.1, WPAndroid 15.9.1, Android 10}

^{play-store-reviewid=gp:AOqpTOEFa_4xGgTSHTiglh4RCq63eL5LeLWEVJeE6RGXo9aJqfqZMwPRu0tCb2jXp1YRnuRhQtBWpYjeTZuFGQ}