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Did you try something like:
```const thing = usernames.apply(names =&gt; {
   return names.filter(filterFunction)
}```

The challenge (and it is a bit maddening as you said) is that usernames is not a `string[]` - it’s an `Output&lt;string[]&gt;` so string methods are not available to it. Therefore, you need to work within the  `.apply()` block to strip that `Output` aspect and get the value as a `string[]` and then you can mess with it.
In the above, `thing` will be an `Output&lt;string[]&gt;` again but it will contain what you want for later use.

Thank you <@U01BSQWRZFA>. I thought I understood using `.apply()` but sometimes it just doesn't seem to work the way I hope it will. I appreciate your explanation. It is helpful indeed. I will work with the suggestion you provided and see where I can take it.