Google added external monitor support starting with the Pixel 8. So, yeah... Most don't support it, but newer ones do!

And I hope you love the case! I also used a Define R5 for my most recent build, a couple years ago. It's solid!

Looks like Thorin wants you to open that up so he can claim his box!

I'd look into tools built for that purpose. For example, vscode's live share feature. Other IDEs have similar features.