I got this error today as well when i made a bundle extension for my app. My solution was to fix the locale files of the liquid content as well as closing {% tagName %} tags properly.
If you have access to an AI coding agent, that will solve this 100 times faster. Give it the verbose logs so the AI can see where it breaks and it will investigate and fix it for you.
I had this done by Claude, but a free solution would be GitHub’s Copilot.
Try this command that worked for me:
My Claude Code told me to run the command:
shopify app dev --verbose 2>&1 | grep -A 20 "graphql.json"
Then it spitted out the exact error that was crashing it:
❌ Error└ [blocks/bundle.liquid] Invalid tag 'schema': unknown key 'presets'