When testing out forms with the Big List Of Naughty strings, cypress itself fails to type the string ‘hasOwnProperty’
Cypress Should be able to type all strings
cy.get(‘input’).type(‘hasOwnProperty’);
cy.get(‘textarea’).type(‘hasOwnProperty’);
Nothing happens, workaround:
cy.get(‘input’).type(‘h’).type(‘asOwnProperty’);
Chrome v68
Cypress v3.1.0
Same with these values
toLocaleString
toString
valueOf
The JavaScript object prototype functions ....
Yes, lol, this is happening.

It is a fun bug lol. The bug is on isSpecialChar and isModifier called from typeChars in packages/driver/src/cypress/keyboard.coffee.
Please note the following behaviour of the Javascript dictionary behaviour:
modifiers = {alt: false, ctrl: false}
{alt: false, ctrl: false}
modifiers["alt"]
false
modifiers["hello"]
undefined
modifiers["toString"]
ƒ toString() { [native code] }
The last one is not ok.

Let me see what I can do there.
@clarmso Let us know if you need any help contributing. Feel free to open a WIP (work in progress) PR that we can help with.
The code for this is done in cypress-io/cypress#3903, but has yet to be released.
We'll update this issue and reference the changelog when it's released.
Released in 3.3.0.
Most helpful comment
Yes, lol, this is happening.