How to get an array of just the keys that have values attached in Javascript?

So lets say I have an object like this:

myObject = {
    key1: "foo",
    key2: "",
    key3: "bar",
    key4: "foobar",
    key5: undefined
}

and I want an array of the keys, but only if the have a value. i.e. if they’re undefined or empty string, I don’t want them included in the array.

Currently I’m using Object.keys(myObject) but this gets all the keys including those that are undefined/falsy.

I completely understand I can likely write my own version of the keys method from Object, but I’m wondering if theres an easier way than that.