secure entry/displayChar support for other mask types

[CuddleBunny]

What problem you are trying to solve?
I have some fields with masks like number that I'd like to use displayChar with.

Describe the solution you'd like
The following should work:

IMask(element, {
  mask: Number,
  displayChar: '#'
}

Describe alternatives you've considered
Some of these fields I can represent with the pattern mask which supports secure entry, but many will not work with patterns.