QuickTime MP4 editing options grayed out on M-series Macs

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Level 1

4 points

QuickTime MP4 editing options grayed out on M-series Macs

Quicktime editing of mp4s with OS 27.0 and 27.0.1 (Golden Gate) results in grayed out options when using my silicon imac or macbook m4.

iMac 24″, macOS 27.0

Posted on Oct 3, 2026 1:31 PM

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Answer 1

Oct 3, 2026 11:49 PM in response to jwh169

Sounds weird. Where does the .mp4 come from? Are its permissions OK? There are many .mp4 flavors like VP9 movie codec that are incompatible with QuickTime Player but even there the Edit options are initially not grayed out, even with Read-only permissions. Does safe boot make any difference?

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Answer 2

jwh169 Author

Level 1

4 points

Oct 5, 2026 9:02 AM in response to Matti Haveri

Thank you Matti Haveri. They are often vimeo movies, but the problem is the same for .mov videos recorded from iphones or videos recorded using Quicktime screen recording. Permissions look fine. You are right, the Edit options are not initially grayed out, but occur at some point during the editing process which always involves splitting and variously involves removing particular sections, and cutting and pasting sections. It goes well at first, but usually fails after a few edit commands (grays out). My only way to continue is to click on done, save and then open the save file to continue editing until it fails again. I have downgraded my macbook m4 to Tahoe and I am completely back to normal there. I have kept 27.0.1 on my m3 iMac where editing continues to fail (so I don't use it anymore except to occasionally try to troubleshoot the problem). Safe boot has not worked so far.

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Answer 3

Oct 5, 2026 9:35 AM in response to jwh169

jwh169 wrote:

Edit options are not initially grayed out, but occur at some point during the editing process which always involves splitting and variously involves removing particular sections, and cutting and pasting sections. It goes well at first, but usually fails after a few edit commands (grays out). My only way to continue is to click on done, save and then open the save file to continue editing until it fails again.

I only do quite simple edits in QuickTime Player. For more demanding lossless straight cut edits I use Avidemux (which sadly is officially still Intel-only) or some other app usually using ffmpeg under the hood.

IMHO QuickTime Player is like Preview, Photos and other bundled apps: a freebie not so robust app just for the basic stuff.

For more demanding lossy edits needing re-encoding I use Final Cut Pro -- iMovie, DaVinci Resolve, Premiere etc are other options.

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