I think I'm missing something with the ManagedPropertyMapping tag on display Templates. Indeed I have this code originally:
<!--[if gte mso 9]><xml>
<mso:CustomDocumentProperties>
<mso:TemplateHidden msdt:dt="string">0</mso:TemplateHidden>
<mso:MasterPageDescription msdt:dt="string">Displays a result tailored for a web page.</mso:MasterPageDescription>
<mso:ContentTypeId msdt:dt="string">0x0101002039C03B61C64EC4A04F5361F385106603</mso:ContentTypeId>
<mso:TargetControlType msdt:dt="string">;#SearchResults;#</mso:TargetControlType>
<mso:HtmlDesignAssociated msdt:dt="string">1</mso:HtmlDesignAssociated>
<mso:ManagedPropertyMapping msdt:dt="string">'Title':'Title','Path':'Path','Description':'Description','EditorOWSUSER':'EditorOWSUSER','LastModifiedTime':'LastModifiedTime','CollapsingStatus':'CollapsingStatus','DocId':'DocId','HitHighlightedSummary':'HitHighlightedSummary','HitHighlightedProperties':'HitHighlightedProperties','FileExtension':'FileExtension','ViewsLifeTime':'ViewsLifeTime','ParentLink':'ParentLink','FileType':'FileType','IsContainer':'IsContainer','SecondaryFileExtension':'SecondaryFileExtension','DisplayAuthor':'DisplayAuthor'</mso:ManagedPropertyMapping>
<mso:HtmlDesignStatusAndPreview msdt:dt="string">http://win2012spstd/sites/publishing/_catalogs/masterpage/Display Templates/Search/Item_WebPage.html, Conversion successful.</mso:HtmlDesignStatusAndPreview>
<mso:HtmlDesignConversionSucceeded msdt:dt="string">True</mso:HtmlDesignConversionSucceeded>
</mso:CustomDocumentProperties>
</xml><![endif]-->
And whatever I do Inside that tag, it doesn't change the way how my result looks. In other words, in can remove every properties:
<mso:ManagedPropertyMapping msdt:dt="string"></mso:ManagedPropertyMapping>
Or add more properties, it doesn't matter.
Could you please tell me what I'm missing?
P.S.: I'm using SharePoint Standard
Ok, I've finally solved that problem. I didn't understand that I needed to create a new display Template instead of editing the default one.