Sounds like you are missing libdvdcss available from:
https://www.videolan.org/developers/libdvdcss.html

Without that installed the system has no way to decrypt your DVDs so 
they will appear pixelated

Brian Cluff

On 8/31/21 8:07 PM, Steve B via PLUG-discuss wrote:
> Recently I reinstalled Handbrake to Linux (Pop OS) hoping to start 
> ripping DVDs again. Previously it was a deb package but it appears 
> Handbrake has moved to Flatpak for Linux distribution.
>
> This version of Handbrake is not working for me and I'm struggling to 
> understand what I am doing wrong. When Handbrake scans the DVD it does 
> not find anything. I have to open and start the DVD in VLC and then 
> Handbrake it will find it in its scan. What it does find shows as 
> pixelated in both the preview as well as any rip it makes for me. I've 
> tried a handful of the presets and no matter what I chose I get the 
> same pixelated output.
>
> Are there any other Flatpak/Handbrake users in this group that have it 
> working successfully for them who can give me some guidance?
>
> Steve
>
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