The addon adds two operators: Deselect Boundary (as the name suggests, the opposite of built-in Select Boundary Loop) and Connect, which performs localized loopcuts on selected faces or edges.
Operators can be found via search menu, or in edit mode menus Select -> Deselect Boundary and Edge -> Connect or Face -> Connect.
This is now an updated version with 2.8+ support, shorter, faster code. The old “Cut Faces” operator has been replaced with the new “Connect” operator. This new operator looks at face selection only if you have face selection mode enabled, otherwise it follows selected edges.
There was a small issue with initial release: forgotten to remove one debug print, thanks to @JA12 for pointing it out. It is now fixed. Shouldn’t be a big deal, but if you use console often, might be a good idea to reinstall.
Is it possible to also add this for edges with a option outset, inset and perhaps in- & out-set with certain distance. This would be very handy and make it a combi off bevel and sub-devide faces