Drupal Canvas Full HTML rollout guide

#devlog #agents #ai

I turned my Drupal Canvas Full HTML notes into a clear rollout guide and backed it with a runnable repo so teams can ship rich editing without breaking permissions.

Why I Built It
Canvas ships with a powerful editor, but Full HTML in Canvas can be risky if the configuration is sloppy. I wanted a deterministic, step-by-step guide that makes the rollout safe and auditable, plus a concrete reference implementation I can point to.

The Solution
I distilled the guide into a predictable sequence and mapped it to actual code:

Validate prerequisites (Drupal 11.2+, Canvas 1.0.4, Full HTML text format)
Install Canvas and Canvas Full HTML
Enable Gin for a consistent editing baseline
Configure Full HTML in Canvas and clear caches
Verify component schemas expose contentMediaType: text/html
Confirm Canvas AI behavior and prompting patterns for safe component use

props:
  type: object
  properties:
    content:
      type: string
      title: Content
      contentMediaType: text/html
      x-formatting-context: block

The Code
I built a small module/demo that mirrors the rollout steps and schema expectations. You can clone it or browse the key files here: View Code

What I Learned

Canvas Full HTML supports Drupal ^10.3 and ^11, but stable Canvas targets ^11.2, so version alignment matters.
The Gin admin theme materially improves the Canvas authoring experience.
Canvas AI is safer when prompts emphasize placement over creation, reducing unintended component generation.