GraphiQL v2 Released 
GraphiQL v2 has been released. This comes with a lot of UX upgrades and puts it on par visually and functionally with Apollo's Sandbox et al.

I would love to see documentation updates that reflect how, or if it's possible, to leverage this new version with the Postgraphile's enhancements.

Given the length of time that v5 has been in development, the slow pace of improvement for v4, and the huge leap forward that GrapiQL v2 provides, information around this in docs at the least is crucial for the user base of Postgraphile.