In SharePoint Online Team sites, how to remove the left navigation from modern pages?

Hi @frob ,

For SharePoint Online modern pages, there are no out-of-the-box approaches to remove the left navigation(AKA. quick launch). The supported way to do this would be to deploy an SPFx extension (so it is applied to all pages in the site) that implements CSS to make the changes you are after. The CSS to hide the left hand nav on a modern page is:

nav[role='navigation'] {  
    display: none !important;  
}  
div[class^='pageContainer_'] {  
    left: 0 !important;  
}   

Moreover, some third party tools may provide you with such option to hide left navigation. For example: How to Hide Quick Launch / Left Navigation from Modern SharePoint Team Sites.
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