Disable <title/> warning when React Helmet is used

[ku8ar]

Disabling this warning:
#4596

We use React Helmet in the project (according to examples/with-react-helmet).
Helmet <title /> is injected into _document using Helmet.renderStatic(). And then controlled by every page.
Everything is rendered correctly. And this warning is really annoying...

[github-actions]

Stats from current PR

Click to expand stats

	zeit/next.js canary	ku8ar/next.js canary	Change
Build Duration	15.2s	14.1s	-1.1s
node_modules Size	40.9 MB	40.9 MB	⚠️ +198 B
Total Bundle (main, webpack, commons) Size	210 kB	210 kB	✓
Total Bundle (main, webpack, commons) gzip Size	69 kB	69 kB	✓
Client _app Size	3.33 kB	3.33 kB	✓
Client _app gzip Size	1.37 kB	1.37 kB	✓
Client _error Size	8.25 kB	8.25 kB	✓
Client _error gzip Size	3.13 kB	3.13 kB	✓
Client pages/index Size	288 B	288 B	✓
Client pages/index gzip Size	222 B	222 B	✓
Client pages/link Size	4.19 kB	4.19 kB	✓
Client pages/link gzip Size	1.85 kB	1.85 kB	✓
Client pages/routerDirect Size	411 B	411 B	✓
Client pages/routerDirect gzip Size	296 B	296 B	✓
Client pages/withRouter Size	393 B	393 B	✓
Client pages/withRouter gzip Size	280 B	280 B	✓
Client main Size	22.8 kB	22.8 kB	✓
Client main gzip Size	7.58 kB	7.58 kB	✓
Client commons Size	184 kB	184 kB	✓
Client commons gzip Size	59.8 kB	59.8 kB	✓
Client webpack Size	1.49 kB	1.49 kB	✓
Client webpack gzip Size	769 B	769 B	✓
Base Rendered Size	1.34 kB	1.34 kB	✓
Build Dir Size	817 kB	817 kB	⚠️ +109 B

Click to expand serverless stats

	zeit/next.js canary	ku8ar/next.js canary	Change
Build Duration	16.2s	16.6s	⚠️ +461ms
node_modules Size	40.9 MB	40.9 MB	⚠️ +198 B
Total Bundle (main, webpack, commons) Size	210 kB	210 kB	✓
Total Bundle (main, webpack, commons) gzip Size	69 kB	69 kB	✓
Client _app Size	3.33 kB	3.33 kB	✓
Client _app gzip Size	1.37 kB	1.37 kB	✓
Client _error Size	8.25 kB	8.25 kB	✓
Client _error gzip Size	3.13 kB	3.13 kB	✓
Client pages/index Size	288 B	288 B	✓
Client pages/index gzip Size	222 B	222 B	✓
Client pages/link Size	4.19 kB	4.19 kB	✓
Client pages/link gzip Size	1.85 kB	1.85 kB	✓
Client pages/routerDirect Size	411 B	411 B	✓
Client pages/routerDirect gzip Size	296 B	296 B	✓
Client pages/withRouter Size	393 B	393 B	✓
Client pages/withRouter gzip Size	280 B	280 B	✓
Client main Size	22.8 kB	22.8 kB	✓
Client main gzip Size	7.58 kB	7.58 kB	✓
Client commons Size	184 kB	184 kB	✓
Client commons gzip Size	59.8 kB	59.8 kB	✓
Client webpack Size	1.49 kB	1.49 kB	✓
Client webpack gzip Size	769 B	769 B	✓
Serverless pages/link Size	342 kB	342 kB	✓
Serverless pages/link gzip Size	87.7 kB	87.7 kB	✓
Serverless pages/index Size	333 kB	333 kB	✓
Serverless pages/index gzip Size	85.3 kB	85.3 kB	-1 B
Serverless pages/_error Size	333 kB	333 kB	✓
Serverless pages/_error gzip Size	85 kB	85 kB	-1 B
Serverless pages/routerDirect Size	334 kB	334 kB	✓
Serverless pages/routerDirect gzip Size	85.2 kB	85.2 kB	-2 B
Serverless pages/withRouter Size	334 kB	334 kB	✓
Serverless pages/withRouter gzip Size	85.2 kB	85.2 kB	✓
Build Dir Size	2.39 MB	2.39 MB	⚠️ +109 B

[timneutkens]

Thanks! This is fine to opt out of the warning.

Just to be clear I wouldn't recommend using react-helmet for most cases in Next.js:

• Bigger bundle size
• More rendering overhead
• Extra implementation overhead

In most cases you can/should use next/head.

[ku8ar]

Thanks for quick merge and info about bundle size.
We plan to use next/head in future version of app, but migration will take a long time. You know how it is...