PNG image upload regression in Microsoft 365 Copilot Chat (m365.cloud.microsoft/chat)

Question

I’m reporting a regression in Microsoft 365 Copilot Chat at https://m365.cloud.microsoft/chat

PNG image uploads previously worked for me, but are now consistently failing. The UI reports either “file type not supported” or “an error occurred while uploading your file”, despite PNG being listed as a supported format.

Environment

• Account type: Personal Microsoft account (Gmail‑backed)
• Copilot surface: Microsoft 365 Copilot Chat (m365.cloud.microsoft/chat)
• File type: PNG
• Browser: Edge

Impact Image upload is a core Copilot workflow for tasks like screenshot analysis and OCR. Without it, Copilot is effectively unusable for my use case. This regression directly affects the value of my subscription.

Request Can this be confirmed as a known issue or regression specific to the Microsoft 365 Copilot Chat surface? If so, I’d appreciate confirmation that it’s being tracked, or guidance on which Copilot endpoint currently supports PNG uploads reliably.

Thank you — I’m happy to provide additional diagnostics if needed.