Are there any flagship real-world Compose Desktop apps? E.g., Flutter has Rive.

Not sure what exactly you mean by flagship real world. This is one of the most advanced I have seen: https://github.com/JetpackDuba/Gitnuro It is a git client. But there are a couple of good ones closed source.

thanks. which closed source good oneS?

I have seen a couple but haven't saved them. I know there is a nice photo gallery around.

I hope you refer to Ashampoo Photos 😉

Yeup, this is it 👆

I started a list here, you might be interested in the projects listed there: https://github.com/sebkur/awesome-compose-for-desktop

Done 😉

Done 😋

My closed-source desktop app Hue Essentials is built using compose

Happy to see Gitnuro mentioned as an example 😄 I'd recommend searching for https://github.com/topics/jetbrains-compose to see more examples