Test environment

Hi,
i just started using backstopjs, and it seems really great, cheers for this cool tool.

I'm not reporting an issue, but rather asking some explanations.
I understand that, when testing visual regressions, dynamic data (eg. data from a database) may be a problem, as they evolve through the time, and will cause some tests to fail, not because the layout broke, but because the data changed.

So i'm wondering about what is the best way to deal with this issue.
It seems to me that the tested app/website should have a test environment, loading static data (that don't change), and that backstopjs should be run against this environment to make sure the data of the tested website don't change overtime.

Is this the correct/ best approach to deal with that ?
if so, is there a common way of implementing that behaviour. The only solution i can think of right now is to pass a GET param to every url (e.g. ?env=test) to inform the app to use the test environment.
But i'm curious if there are some different / better solutions ?

Thanks in advance !