What are the differences between using attachShadow with the "mode" set to open compared to closed

I've recently delved into the world of Shadow DOM through some casual video watching. It seems like many people are quick to dismiss this feature, with comments like "Just keep it open" and "It's less flexible when closed." 

attachShadow( { mode: 'open' } )

Can someone please explain in simple terms what this piece of code does?

Could an HTMLVideoElement be considered a closed Shadow? My understanding is that you can't create a new shadow because one already exists, but you're unable to access it. Is there any connection here?

Appreciate any insights. Thanks!

javascriptshadow-dom

Answer №1

To understand the distinction between the modes of closed and open, refer to this informative answer:

Explaining the variance between open and closed shadow DOM encapsulation mode.

A <video> element utilizes a user-agent shadow DOM, representing a unique type of Shadow DOM that functions similarly to a closed one. For more insights on the user-agent shadow DOM, check out this discussion:

Strategies for accessing elements in the shadow root using JavaScript.

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