SharePoint thumbnail change breaks some Power Automate flows
Reviewed by Helen Jones
Microsoft began changing the thumbnail data returned by SharePoint triggers and actions on 1 September 2026. Existing Power Automate flows that pass a thumbnail URL into another action may now receive an invalid URL; Microsoft directs makers to the newer Get file thumbnail action, which returns the image instead.
Before this change, a maker could take the thumbnail URL returned by actions such as Get items or Get files and pass it into an email, approval or document step. The flow could keep running for months without drawing attention to that dependency. Now those downstream steps can fail even though the SharePoint trigger still succeeds. This is the awkward kind of break that may look like a problem with the email or file action, so checking the thumbnail input first can shorten the investigation.
Analysis
Open any flow that uses SharePoint thumbnails and inspect the first downstream action that consumes the thumbnail URL. Replace that input with Get file thumbnail, then run one test using a real file before relying on the flow again.
Source note
Pulse published by Collab365 Spaces, reviewed by Helen Jones on . Cite as "SharePoint thumbnail change breaks some Power Automate flows", Collab365 Spaces.