iMovie 10.1.13 upgraded uninstalled 2x. Start to edit movie, then tools break into colored blocks on screen and not responsive,

Yes, the only solution that appears to work (as described in several replies above):

Go to System Preferences->Accessibility->Display and turn off both reduce transparency and increase contrast.

Crazy that Apple does not have this tip in their support site for resolving iMovie issues.

To repeat my earlier suggestion, I would call Apple Support. I have never before seen the issue that is displayed on your screen shot, so I am thinking that it might be related to the recent upgrades and updates.

Since you already have tried a reinstall of iMovie, you could try a few other diagnostic procedures:

1. Try opening iMovie while holding down only the Option key, and selecting to creating a new library in which to open. See if the problem replicates in the new library.
2. Try booting up in Safe Mode and, after everything loads, reboot in normal mode. Now see if iMovie functions properly.
3. Try opening iMovie in a new or different user account. You can create a new user account from System Preferences/Users and Groups.

-- Rich

• This seems to be my situation also ("only the "Reduce transparancy" was checked. Unchecking that did the trick.")
• THANKS so much for posting these workarounds to fix the problem with the menus; until finding this article, I was "dead in the water" with producing movies.

I get these colored blocks (they're actually pink on my screen, but appear to be green in the screenshots I took) when I want to use the menu bar inside a project in iMovie 10.1.13. I then updated to Catalina, but the problem remained. It only happens when editing a project, not in the overview screen. In this state, the software is not usable any more. Any ideas? Don't think it is possible to downgrade to the last working version.

I see the same behavior. iMovie 10.1.13 on a MacBook Pro (15 inch), macOS 10.14.6. iMovie worked fine before the upgrade. Now the screen is filled with graphics tearing and large blocks. iMovie is completely unusable. Closing the app makes the problem go away. Tried rebooting, tried using a different/new iMovie library. Nothing helped.

Try opening iMovie while holding down the Option and Command keys and selecting to delete preferences in the box that appears. iMovie will open in a new library. Reopen your old library to get back to your projects. Now see if version 10.1.13 works properly.

-- Rich

iMovie 10.1.13 has just been released and there may be some glitches until they get worked out. I suggest that you click on the "Contact Support" item in the upper right hand corner of this forum's screen. Follow the screens to navigate to iMovie. You should find a telephone number there to call Apple Support. Those folks are pretty knowledgeable and you may be able to get some guidance there.

-- Rich

I think it may be related to the graphics system? I have the same problem on this machine with both Mojave and Catalina:

iMac (27-inch, Late 2013), 3,5 GHz Quad-Core Intel Core i7, 32 GB RAM, NVIDIA GeForce GTX 775M 2 GB

Tried to reinstall Imovie, tried new library, tried library with only one project, tried deleting prefs etc. No difference.

Tried the same library with only one project on this with Mojave: Macbook Air (13-inch, Mid 2012), 2 GHz Intel Core i7, 8 GB, Intel Graphics 4000. No problem!

Apple support in Denmark? Not really...

I tried the same as you. I have problem with video in timeline. It is not in sync. The sound is in sync. Got the problem after opdating to 10.1.13.

Jeg ringede til Appel support, men de foreslog det jeg havde prøvet, så jeg tror det er et problem der ligger i den sidste opdatering der kom den 7. oktober.

I know, annmou. Now Apple Support Denmark know too :-) But as suspected they can't tell how or when they (or even I) will be able to solve it. Does anybody know, if the previous version of Imovie works under Catalina?

I can confirm that I too have the same problem (10.1.13) displaying when you attempt to access any pulldown menu, or indeed DOCK item. In my case purple blocks etc looking similar to what Chris Torrence was showing. Another clue might also be that, for me at least, this has been happening in the same way, when using VLC player (VideoLan) for some while now. No older versions seem to correct the error!

However, I have already reverted to iMovie 10.1.12 and NO problems, but as you may have already guessed, you can no longer access the iMovie library created (modified) by 10.1.13. For me though, the previous version works OK every time i use it.

It does seem to be related to graphics in some way or another. I'm still on Mojave and will be unable to update anyway! iMovie and VLC are the only two apps to cause this problem.

I can confirm that using Time Machine to go back to iMovie 10.1.12 fixes the issue. I also had to restore my older iMovie libraries since those were no longer compatible with 10.1.12 version.

Be sure to turn off auto updates on your Mac (System Preferences->Software Update), otherwise it will just re-apply the 10.1.13 update... Sure hope Apple fixes this soon!