WordPress fails to embed video URL on specific theme

My developer created custom theme for WP, and for some reason Wordpress fails to embed video URL on user-end. Everything is fine with Default WP themes, also video is fine on visual mode, but if I try to switch to this theme- I see only the video URL, but not embed video.

Looks like we need to add something to our theme, but can't find any manual - what we need to add to function.php?

thanks

Topic oembed youtube themes Wordpress

Category Web

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