I made a pattern that rubber key touches, but the cupper doesn’t open.
The preview of the pad shows that it only defines the small circle that is exposed on your product.
You will need to either add a mask only circular pad on top of your copper definition (the graphics you used to make the pattern) or you need to combine the pattern and the anchor pad into a so called complex pad such that it can control the layers of the pattern.
I suspect that using a separate cicular mask only pad is what you want as you will most likely naot need mask between the fingers of your pattern.
My circular pattern shows only F_cu and no mask button. I’m using kicad 5.1.
How do I connect the dot and my circle?
Disclaimer: The below is valid for KiCad 5.1.x.
In the footprint editor:
Select one of the pads (left click)
Add all the graphic copper features connected to this pad to the selection (with shift click).
right click -> create pad from selected shapes
I however suspect that you are better off adding a circular mask only pad to your center feature as you might not want to have mask in between your fingers. Here the screenshot of the two possible results in the 3d viewer (right most is the one with a circular mask only pad added, left most is similar to what you currently have)