Dash fastSeek issue in safari

[marcobouwmeester]

Description

When in safari, we are encountering an issue where the progress bar does not work properly when using Dash. While playing the video, when we click in the progress bar and then click before the current time, the video playback stops and shows strange behaviour. I included a potential fix and reproduction steps here: https://codepen.io/MarcoTradecast/pen/ZEKoJYb. For the fix I disabled fastSeek only for safari, since fastSeek is also possible for Firefox.

Steps to reproduce

Explain in detail the exact steps necessary to reproduce the issue.

1. Open https://codepen.io/MarcoTradecast/pen/ZEKoJYb in Safari.
2. Change/revert the code as described in the comment.
3. Play the video and click (no dragging) to around 70% percent of the video in the progress bar.
4. Now click near the beginning of the video in the progress bar (once again no dragging).

Results

Expected

The video should go back to the desired timestamp.

Actual

Video playback stops and currentTime is not being updated. Play/pause button is also not responding anymore.

Error output

There are no errors

Additional Information

versions

videojs

7.13.3

browsers

Safari (in my case 14.1.1)

OSes

macOS Big Sur 11.4

plugins

No additional plugins are being used in the example.

I hope this issue is clear enough to reproduce :-)

[welcome]

👋 Thanks for opening your first issue here! 👋

If you're reporting a 🐞 bug, please make sure you include steps to reproduce it. We get a lot of issues on this repo, so please be patient and we will get back to you as soon as we can.
To help make it easier for us to investigate your issue, please follow the contributing guidelines.

[gkatsev]

I believe that this will be fixed via #7527