The process of building custom applications and tools that interact with Microsoft SharePoint, including SharePoint Online in Microsoft 365.
Hi @Rising Flight ,
Thank you for posting in this community.
You want to change the font size for an entire specific SharePoint site (similar to changing the theme of a site, not for a specific page), right?
Normally, you can use custom CSS to change the font size on a specific SharePoint site(This extensibility option is only available for classic SharePoint experiences. If you're using modern experiences in SharePoint Online, you can't use this option).
In summary: If you are using the modern experience in SharePoint Online, there is no way to change the font size for a specific SharePoint site.
As a workaround, Browser Zoom Feature: If you need a quick and temporary solution, you can use your browser's zoom feature to increase the font size. Press Ctrl + (or Cmd + on Mac) to zoom in.
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