Adding a Connected Clip Transition freezes timeline playback

Has anyone had this issue?
Occasionally, when I add a transition to a connected clip I can no longer use the timeline. Clicking into the browser or hitting the tab key will get it out of this "locked" state.
In the video I go into detail and demo the behaviour. 

Have you tried deleting the FCP preferences?

Thanks. That appears to have fixed it. I cannot make it occur anymore in my quick tests. In all my watching and reading fcpx stuff this is the first time I've ever heard of the "delete preferences" fix. How often do you use this procedure in your everyday use of fcpx?

Deleting FCP's preferences is actually a common troubleshooting step. Another step would be to delete FCP.app and download and reinstall it, though I usually would only do this after trying to delete preferences and doing some standard macOS "cleaning" steps (as described below).

I often also suggest to restart one's computer in Safe Mode (hold shift down on powerup/startup until the login screen appears and "Safe Boot" is shown at the top of the screen, after which you'd log in and then restart the computer normally). I usually try to do a safe mode startup every week or so, or when trying to troubleshoot a specific issue, as it cleans temporary files, font caches, etc. from macOS. Sometimes, resetting the NVRAM ("zapping PRAM") or resetting the SMC can help, as well (especially to help reset USB and TB ports and other HW devices).

Start up your Mac in safe mode - Apple Support

www.macworld.com/article/224955/how-to-r...am-pram-and-smc.html

It's is also helpful to turn off any sort of automatic system software updates, as well as automatic updates to Mac Store apps. Anyone who makes money using an NLE (or their computer, for any task) should avoid upgrading during a project, as any macOS, application, or third-party update can destabilize a working system.

For example, I recently experienced weird behavior with macOS after updating from macOS 12.5 to 12.6. Doing a safe mode startup, zapping NVRAM/PRAM, and resetting the SMC cleared the issue.

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Because I'm pretty "OCD" about keeping my system "clean" and maintained, I rarely delete my FCP preferences. I also use Digital Rebellion's Pro Maintenance Tools, which includes a preference manager.

www.digitalrebellion.com/promaintenance/

Glad to hear that deleting the FCP preferences helped...

Cheers.

Thanks for the tips. This all seems strange to me, I've only recently upgraded to the Mac mini and FCPX from a 2008 Mac Pro and FCP6. My old setup was super stable and hardly ever crashed. I've been using Macs since the 90s, I guess I had just forgotten the good old days. (like doing a complete restart before doing a long render in AE).

For context, in the decade I've been using FCPX, I've had to delete preferences exactly 2 times. Reinstalled once, but the problem was elsewhere.

But I also do regular system maintenance, keep my files carefully organized, and run a lean edit machine. Office apps live on the laptop, nothing runs in the background unless necessary, and only for as long as necessary. And no Chrome, either.