Sure, it's a flag, but Nerv does have a test suite (with 96% coverage) that proves it runs across all browsers. I'm sure the marketing site does not have a test suite like that. You can't hold it to the same bar.
That's fair. I'm just giving honest feedback. I understand Nerv is open source and not being built by a large entity like Facebook. It's also likely a nice library. So sure, I should cut them some slack. But at the same time, there's a lot of React clones to choose from, and seeing a simple error like this right out of the gate is off putting.