Can't have webp and video previews working at the same time

I wanted to enable video thumbnails so I installed ffmpeg in my container image using a Dockerfile and added this to my config.php:

'enable_previews' => true, 
'enabledPreviewProviders' => 
array (
 'OC\Preview\Movie',
 'OC\Preview\PNG',
 'OC\Preview\JPEG',
 'OC\Preview\GIF',
 'OC\Preview\BMP',
 'OC\Preview\XBitmap',
 'OC\Preview\MP3',
 'OC\Preview\MP4',
 'OC\Preview\TXT',
 'OC\Preview\MarkDown',
 'OC\Preview\PDF'
),

This works both in docker version (if you install ffmpeg) and on regular installs BUT the moment you add this block of code to your config webp previews stop working! I have added ‘OC\Preview\WEBP’ to the array to see if works but it doesn’t. If I remove this block of code from the config file webp previews start working again but video previews do not. Anyone knows how can I have both webp and video previews working at the same time?