Is it planned to have a “displayed by default” extension?
Or a potential solution would be to still have the video components system as it is, but to only one of them at the time, like a video overlay but the video component extension would have much stricter rules in term of design UI/UX. For example, these extensions should not have a button to click to open them.
And we could still add the extension sidebar for extensions that previously required a button to open
No, there is currently no plan for a “displayed by default” option for component extensions. As mentioned in my reply to your other question, we are leaning toward the idea of a notification system for an extension that must present information to users while collapsed.
Also some other questions:
If a viewer opens an extension and moves the mouse out of the player, will the extension still be displayed?
Yes, the extension will remain open if a user opens it and mouses out of the player
Will the sidebar always be on the right? Or can the streamers set it on the left, bottom, top?
The plan for initial release is that the dock will always be on the right. The ability for a streamer to configure this is another one of our possible followup features.