1. Activating a Sitemap

Technically, sites in XML format are where Google's indexation robots' attention is drawn to. The Sitemap system indicates which pages of your website should be indexed, and when their last update was. Basically, its purpose is to lessen the work of Google robots.  

Go to the menu Publish > Administration > SEO, in the Sitemap tab.  

By default, the sitemap is deactivated.
Activate the sitemap by clicking ON.

2. Declaring a Sitemap to Google

To declare your sitemap to Google, go to your account in the Google Search console :
http://www.google.com/webmasters/tools/  

Log into your account, then click the red "Add a property" button. A new window "Add a property" will appear.

Put the URL of your web app next to the Website menu in the dedicated field : 

Click "Add"

You have the following options : "Recommended method" or "Alternate methods".
You must copt the HTML tag provided by Google.

Once back in your back office, in the menu Publish > Administration, SEO, in the Sitemap tab, paste the Google tag in the Google Meta Tag field, then click Save. 

You must update your app for this to be taken into account.
To do that, go to the menu Publish > Update > Changelog, then click the green button Update > Next.

Wait for the update to be complete (this can take several minutes).  

Then return to the Google Search console, click the red "Validate" button to validate your new property.

Once your web app has been validated by Google, click the menu Exploration > Sitemaps (still in the Google console).  
Then the red button : Add / Test sitemap

Get the end of the sitemap URL (front-assets/index-sitemap.xml) in the menu Publish > Administration > SEO, in the Sitemap tab, in your back office.  
Paste this in the field stated by Google, then click "Send". 

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