Forum Discussion
Injecting javascript into SharePoint online communication site
Hi All I need to inject some javascript into all sharepoint online site collection pages. I managed to do it in Team site by adding javascript file link in to a master page, but cannot find the way ...
Beau Cameron Thanks
So we cannot really add much custom scripts into modern sharepoint? 
RomanRomych Correct. As mentioned, you can use SPFx Application Customizers, but you shouldn't inject JavaScript to customize out of the box components. It's only supported to inject code into pre-defined placeholders on the page (top and bottom).