Does the screen recording (Shift + Cmd + 5) on macOS Mojave really work?

[fargo3f]

I have an iMac 2019 27" (Retina 5K) and it came with macOS Mojave 10.14.4. I tried to record the News from the YouTube in full screen, I always end up with only 5mins clip instead of a full 30mins clip. I even update it to 10.14.5, same result. Out of curiosity, I tried it with the QuickTime Player, it was slightly better (7-8mins clip out of 30mins). I notice that the longer I have the screen recording running, the smaller is my recording, e.g. 9s out of 1hr clip. Really strange. Does anybody have this same problem? Thank you.

 

[Just_Me_D]

After reading your post, I begin recording the screen of my MacBook Pro, currently running macOS Mojave and I let the recording go on for almost 10 minutes before I stopped it. I don't have any reason to believe it wouldn't have continued recording.

I'll be reinstalling macOS Catalina later this afternoon and I'll do another screen recording experiment afterwards if I don't forget.

UPDATE: While sitting comfortably on my sofa and reading online articles, I was wondering why my MacBook Pro was getting a bit warm. It turned out that I was still screen recording. When I stopped the recording, the time was at 30:08 and the file size was 2.28 GB.

 

[fargo3f]

Thanks for the reply and thanks for spending the time to test it out. Really appreciated it. I agree with you that there's no problem with the MacBook Pro. I tried it on mine and I was able to record it for almost two hours. No issue.

But here is the thing. I suspect the problem lies only on '5K Retina iMac' with 'macOS Mojave.' Very specific. When I try to connect it to an external monitor (1920x1080), I was able to record it for almost 30mins. No issue. But when I try to record it without connecting to external monitor, the recording crashed.

I wonder if anybody has an iMac 2019 (5K Retina 27") with Mojave installed, and can confirm that this is an issue? I just bought this Machine a week ago, and if there's an issue, I need to return it. Thanks.

 

[Just_Me_D]

You’re very welcome, and your suspicion in regard to the iMac is quite interesting. Hopefully those who use one will test for you to either confirm to refute.

 

[fargo3f]

UPDATE: Apparently, this is a known issue for quite some times since the beginning of macOS Mojave 10.14.1. Up till now, it hasn't been fixed. They won't confirm that this problem will be fixed in the up coming macOS Catalina.