Custom block triggers no-multiple-template-root

[jods4]

Checklist

• I have tried restarting my IDE and the issue persists.
• I have read the FAQ and my problem is not listed.

Tell us about your environment

• ESLint version: not sure, version bundled w/ Vetur?
• eslint-plugin-vue version: same
• Node version: 15.3.0
• Operating System: Win 10

Please show your full configuration:
No config.

What did you do?
I'm trying to use a custom block in SFC.

I did register it in Vetur customBlocks, compiled the grammar and restarted, which now highlights properly.

<route>
{ title:  "abc" }                             
</route>

<template>
Page A
</template>

<script>
export default {
  setup() {}
}
</script>

What did you expect to happen?
No eslint error

What actually happened?
eslint-plugin-vue reports vue/no-multiple-template-root, see screenshot:

[ota-meshi]

Thank you for this issue.
I can't reproduce the problem. Do you get the same error from ESLint or vscode-eslint? If not, it may be a Vetur specific issue.

[ota-meshi]

If you have the same problem with the CLI, reopen it.