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node_modules/gatsby-plugin-react-helmet/README.md

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+# gatsby-plugin-react-helmet
+
+Provides drop-in support for server rendering data added with
+[React Helmet](https://github.com/nfl/react-helmet).
+
+React Helmet is a component which lets you control your document head using
+their React component.
+
+With this plugin, attributes you add in their component, e.g. title, meta
+attributes, etc. will get added to the static HTML pages Gatsby builds.
+
+This is important not just for site viewers, but also for SEO -- title and description metadata stored in the document head is a key component used by Google in determining placement in search results.
+
+## Install
+
+`npm install --save gatsby-plugin-react-helmet react-helmet`
+
+## How to use
+
+Just add the plugin to the plugins array in your `gatsby-config.js`
+
+```javascript
+plugins: [`gatsby-plugin-react-helmet`]
+```
+
+## Titles don't appear when opening in the background, while using `gatsby-plugin-offline`
+
+If you're using `gatsby-plugin-offline`, you might notice that when opening a link in the background, the title doesn't appear in the tab bar until switching to that tab. This is an [upstream issue with React Helmet](https://github.com/nfl/react-helmet/issues/315); however, it can be worked around by passing the `defer={false}` prop into your `Helmet` component. For example:
+
+```javascript
+<Helmet title="foo bar" defer={false} />
+```
+
+## Compatibility with React 16.8 useEffect hook
+
+If you are using this plugin with React hooks, you may notice some errors like `maximum call stack size exceeded`. To ensure everything is running smoothly when using these technologies together, make sure to validate the following:
+
+- You have updated to the latest version of `gatsby-plugin-react-helmet`
+- You are using version 6.0.0-beta or later of `react-helmet`
+- You are importing React Helmet using `import { Helmet } from 'react-helmet'` rather than the old `import Helmet from 'react-helmet'`
+
+## Examples
+
+- [GatsbyJS.org](https://github.com/gatsbyjs/gatsby/blob/master/www/src/components/site-metadata.js)
+- [Jason Lengstorf personal website](https://github.com/jlengstorf/gatsby-theme-jason-blog/blob/master/src/components/SEO/SEO.js)