En Croissant: The Ultimate Chess Toolkit

What's the game shown in the thumbnail picture of the article?

we have to enable multiple lines for a engine analysis always it doesn'tmake it default

Is there an option to see your common mistakes in certain openings?

If not, this would be the best upgrade. I've seen this possible on another chess website. Don't know the title, but in practice there was message: You made this error in 45 games playing this opening.
After that you were able to practice those moves.

beautiful app . Thanks frankwillow