JavaScript Calculator Accepts Invalid Input

Hello everyone.

I have found that the application [ https://www.freecodecamp.org/learn/front-end-development-libraries/front-end-development-libraries-projects/build-a-javascript-calculator],[ https://javascript-calculator.freecodecamp.rocks/ ] has some bugs:

Uncaught SyntaxError: Unexpected token ‘*’

input: *2=

Uncaught SyntaxError: Invalid regular expression: missing /

input: /2=

Uncaught SyntaxError:Invalid regular expression flags

input: /2/2=