This PR adds a configuration option to control the preloading of video data on
page load with the HTML5 'preload'[1] attribute on the `<video>` element.
The option is enabled by default, meaning that the `preload` attribute's value
will be 'auto'. If users want to prevent preloading of video data, they
can disable the option, which will set the attribute value to 'none'.
[1](https://www.w3schools.com/tags/att_video_preload.asp)
Closes issue 4110
Trying to watch an already watched video will make the video start 15
seconds before the end of the video. This is not very comfortable when
listening to music or watching/listening playlists over and over.
Multiple users have reported that the fields parameter is slowing down API
response times significantly. As most API endpoints are already optimized to
make as few requests as possible to Youtube, there is no point in limiting the
output. Furthermore, the added processing might be part of the broader memory
leak problem (See 1438).
In addition, the small increase in data output is not much of an issue compared
to the huge video proxy that lies next to this API.
No related issue tracked
Fix#4110 by adding an option to control the preloading of video data on
page load. If disabled ("false"), the browser will not preload any video
data until the user explicitly hits the "Play" button.
If enabled ("true"), the default behavior will be used, which means the
browser decides how much of the video will be preloaded.
The fast forward/backward seconds will be adjusted according to playback rate (same as YouTube app behavior).
5 seconds is used when the playback rate is 1x. Previously it was 10 seconds. I believe most of the users watch videos at 2x, so the change will not be obvious.
