Blocks field breaks after adding Video blueprint

Kirby 3 Issues 🐛
1

This began as a strange error on a site I was working on (3.8), and after trying to reduce it to its lowest denominator (in terms of setup) I was also able to reproduce it on a plainkit install.

  • Install Kirby (3.7.5)
  • Add a custom blueprint for site/blueprints/blocks/video.yml
  • Create a Video block

When I follow those steps, regardless of what the contents of video.yml are (empty, the default content, or my own custom blueprint) I start to see this error where the Blocks field should be:

Screen Shot 2022-10-04 at 6.37.23 PM
Screen Shot 2022-10-04 at 6.37.23 PM788×150 4.63 KB

After refreshing the page, it switches to this:

Screen Shot 2022-10-04 at 6.37.30 PM
Screen Shot 2022-10-04 at 6.37.30 PM822×144 4.99 KB

This seems such a big deal that I thought surely there’s no way it’s an actual bug, yet I really cannot figure out what else it would be, and was able to reproduce on a plainkit install. Apologies if I’m overlooking something super obvious, I’m just very stuck!

2

I think I could narrow it down to the inclusion of preview: video in the Block custom blueprint. I made my own custom block (basically recreating the Video block) to circumvent the issue in the meantime, and ran into the same thing.