Hi JiMu
A well-written post and you have highlighted the challenge and the need for Chess.com to offer a stream-friendly layout.
I have, just 4 hours ago, managed to craft this chess.com chess board that is consistent in placing and margins, be it Play, Play Live or Analysis mode. It's not perfect, but it's close to what you want as a streamer without having to share the entire screen. This is a minimalistic design using partial-true-type-font consistent text content, and lots (and I mean LOTS!) of CSS overriding with Stylus and a bit of TamperMonkey. Plus some greenscreen trickery to hide all other elements of chess.com, and to show up only the chessboard, pieces, usernames, ratings, nation flags and timers.
The best part is that I am able to switch scenes on my OBS and transition seamlessly to a Lichess.org chessboard with everything else the same. Of course I duplicate my chess.com Scene for a Lichess version which is no big secret, but it gives the illusion that I am able to switch between chess.com and lichess seamlessly.
In your post above, you mentioned that the core issue which is the Analysis mode layout shifting away from normal Play mode screen. This screwing up the streamer's nicely-crafted layout, every time. For me, I eschew showing the detailed analysis screens. I have done CSS overriding which presents the analysis right panel's text and content in LARGER fonts, which is great for a viewer watching a Twitch stream on his smartphone or tablet, but now I've decided not to show that. Instead, I rely on the evaluation bar (which shows a value anyway) and the on-the-chessboard arrows, blunder symbols and excellent move symbols, and my live commentary as analysis fodder. After all, a Twitch viewer won't be so interested to follow all the nuances of variations and sub-variations of the detailed analysis panel. They are more interested to see you play games. Just my opinion here.
So my give-away here (for you to take-away) is this: if chess.com doesn't give something to you, make it happen with existing free tools. With Stylus, TamperMonkey and CSS overriding, now ANYTHING is possible. If you want to know more, please do post a reply in this thread, or you can DM me.
Cheers and regards
Frankie Kam
Malaysia
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