Oh, systems use the ampersand to denote plurality.

We&, you&, etc.

Microsoft has a hard time with the concept of consent.

Oh good! If it can fit without deforming the plastic inside the opening, then that should be good.

Here is the source code. Might as well. If you want circles instead of hexagon, you can remove ", $fn=6" on line 9. Or experiment with the parameters.
tssrenia.us-east-1.linodeobjects.com/stopper.scad

A file format that describes a 3D object. A slicer software can then render the file into code for a 3D printer to generate it.

Sure, let me know! I would be happy to do modifications and rerender, or share the source code. It is 9 lines of code in OpenSCAD and easy to tweak.

Oh, I am not looking to make money. If the stopper STL interests you, here it is. Just make sure to auto-orient it so the cap is flat on the plate. The cap has a hexagonal shape to prevent it from rolling away when placed on a table.
tssrenia.us-east-1.linodeobjects.com/stopper.stl

An insert for a Kaweco Supra tinbox, to better fit larger pens like the Opus 88, and an short international cartridge plug.

There is another 'stopper' STL available out there, but it busted the lip of my cartridge, and I decided to make my own. One with taper to fit better.

I will cherish them forever ;;

taaaaaaaab... O_o

Evacuation safety that is second to none, guaranteed to be under regulation 90 seconds!