Revision history [back]

Use unique key props: Provide unique key props to each instance of the component with the duplicate tag.
Use React-Headroom: Using React-Headroom with React-Helmet will solve this problem, as it will create a wrapper around the Helmet component that will ensure that only one instance of each tag is present in the head.
Remove duplicates manually: You can remove duplicate tags manually by checking the head tags using developer tools, and removing duplicates from the code.
Use a server-side solution: Another option is to use a server-side solution that will dynamically generate the head content and eliminate duplicate tags.