Version

3.0.4

Steps to reproduce

app.config.isCustomElement = tag => tag.startsWith('x-') This configuration alone has no effect, and then I did a certain vue.config.js It can be realized that there is no warning in templet, but if I use JSX syntax, it will still prompt that the component cannot be parsed. Is there a solution?

What is expected?

Normal pre resolution without warning

What is actually happening?

No pre resolution

Read and follow https://new-issue.vuejs.org/?repo=vuejs/vue-next#why-repro