A compelling update for SharePoint Online just in. The service will now support in-browser viewing of PDF files.

We've received a lot of feedback noting PDF viewing was limited while a number of customers expressed that they did not want PDF files to be downloadable to user’s desktops.

Clicking a PDF document stored in a SharePoint Online library....

....will now simply launch the file within your Internet browser. This too applies to PDFs embedded as attachments within list items

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