Symptom
The error message "Uncaught InvalidCharacterError: Failed to execute 'createElement' on 'Document': The tag name provided ('components/custom/index') is not a valid name." is displayed when createElement is run.
Possible Causes
The is attribute does not support the component path. The value must comply with the HTML Standard, starting with a letter and containing hyphens (-), dots (.), digits, underscores (_), and lowercase letters.
Solution
Use the name of a registered component. This applies to the skeleton format when converting mini program code to ASCF code, in which case you can delete the is attribute.