How to call String.prototype.trim (or any other prototype function) as shown in the documentation example?

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This will probably help you to get a solution faster.
For bugs, it would be great to have a PR with a failing test-case.

I have been trying the example from the docs calling `String.prototype.trim` to work, but it does not seem to return the desired result (https://handlebarsjs.com/api-reference/runtime-options.html#options-to-control-prototype-access).

https://jsfiddle.net/3yahoj1d/

Can anyone explain why the result prints as `[object Object]` to the console when `typeof result` returns `string`, or how to get the example to work?

I have also asked this on StackOverflow (https://stackoverflow.com/q/67416982/5115898) so feel free to close this issue if this is not a problem with handlebars itself.