Background video not working for small windows

Hello, i’m using video background and it actually works awesome as it shows the video exactly how i want it to be. But i have one issue: when i reduce the horizontal size of the browser window to the half of the screen, the video is not showing up. I know that it is disabled for mobile but it in this case it would be nice if it worked for desktop if the window is not maximized/small sized. How can i do that.

2. If it is possible to make the video available for mobile (even with a play button would be fine, i’m glad to know how it can be done.

Tank you for your help

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