GiGs said: There is a way to test changes, but you have to be a Pro subscriber. That's irritating. Yes, sorry, that was me being vague - I meant, no way to test anything with my Base account. I think the Custom Sandbox is a great tool and since it has no value to any user who isn't developing a sheet, it doesn't seem like there is a solid reason not to make it available to other tiers. If the intent is limiting pull requests then that seems like a counter-intuitive way of going about it - if the site makes its money with subscriptions, then one of its features shouldn't rely on not having too many, right? Andreas J. also made some (imo) good suggestions for solving that in a comment earlier: Giving preferential treatment to community/peer-reviewed Pull Requests (i.e. someone have checked the PR and given an approval) Giving a limited number of community contributors "triage" level access to the repo, granting them the options to open/close PRs/mark as duplicates, assign issues/labels, make PR review request.