I have to send notifications to agents about some logic rules, like notifications, and not-interactives messages

I am trying to add a link on the left hand side navigation that opens a specific record.
The following code works, however it opens the whole application in the window (with a second navigation etc.) rather than just the record.
I have included the commented out line which works to open the record in a new tab, but I would rather stay in the main application.