Sidebery is fantastic, but I do feel like it's making things a bit slow. I might be prepared to give up on panels and nesting if I can get better performance. (And possibly the Tab Groups work can replace my use of panels.)

Sidebar makes my Firefox pretty slow at startup and has a few bugs. I would love a native alternative with similar features. Namely I would really like vertical tabs that aren't a sidebar because I want to be able to use sidebars without hiding my tabs... But seems like this new implementation is also a sidebar.

Maybe the native implementation is lighter, but yeah, I get it