Glad you got it sorted out! The Superpowers plugin does use the session-start bash script as a hook, and Windows doesn’t know what to open it with, so you get that popup.
If you want to add the plugin back later, you don’t have to remove it. You can create a PowerShell wrapper instead. There’s a detailed guide here: Windows "Select an app to open" dialog triggers when opening AI chat (.sh file handler issue) - #8 by Emrah
Marking this thread as solved.