Deleting keys from browser is a dangerous operation, we will add it when we have a proper flow in place, like "please make sure you export your keys first" etc. Btw you can already do encrypted nsec export (nip49) in key settings, you can do that and then just clear the browser data for nsec.app, and then import back only keys that are needed, all apps and connections should be synced back from relays.  

 Ok, thanks for the update and tips!