I try to copy and paste a pdf directly from windows explorer into a text webpart in Sharepoint and it just sittings in a 'pasting...' status until the site timesout.
Any ideas why or if this is even possible?
I have ruled out proxy blocking etc
You can't add a PDF file into a TEXT web-part. Only images are supported.
To add a PDF file into a modern page please follow this (Use EMBED web-part) https://www.aerieconsulting.com/blog/how-to-embed-a-pdf-in-a-modern-sharepoint-page