PowerPoint lag on Mac after Tahoe update, images/videos

Hi everyone,

I’m having a very specific issue on one Mac after upgrading to macOS Tahoe:

Problem

• Microsoft PowerPoint on my Mac becomes extremely laggy/unresponsive as soon as I copy an image to the clipboard and try to insert/paste it into a slide.
• Inserting online videos (e.g., YouTube links) also “loads and loads” and often ends in a failure.
• PowerPoint works normally on another Mac (same Microsoft account, same files) that is still on macOS Sequoia.
• Other general troubleshooting (clearing cache, etc.) did not help, and by elimination it seems tied to the OS/version on the Tahoe Mac.
• Besides this, PPT works normal. If the image is in the Slideshow I can edit it, paste it to other slides as well. Just adding new stuff is lagging to no end

What I’m trying to achieve

Before doing a clean install/downgrade to Sequoia, I’d like to try any realistic fixes (e.g., system reinstall over the top, known clipboard issues, permissions, graphics acceleration, etc.).

What I’ve tried

• Restarting PowerPoint/Mac, trying different presentations and a new blank deck
• clearing Office/PowerPoint cache and basic Office updates - de/reinstalling PowerPoint
• Problem persists

System details

• Mac model: MB Air M1, 2020
• CPU: Apple Silicon M1
• macOS version: Tahoe 26.2 (25C56)
• PowerPoint version: 16.105.3

Thanks a lot for any ideas — I’m trying to avoid a full reset if possible.