MacOS Mojave - Brief Black Screen after Login

Venderious

macrumors regular
Original poster
Dec 15, 2014
125
77
Groningen
Hello.

After the recent update to MacOS Mojave, I've been experiencing some issues. After bootup, the login screen appears and logs me in like normal. After login, however, a black screen appears followed by the Apple logo. Only after the Apple Logo shows I am on the homescreen. Does anyone know how to fix this problem?

Below is the order of the bootup, only after the Apple logo I'm greeted with the homescreen.
 

josduc

macrumors member
Oct 8, 2010
37
8
Glad to see I'm not the only one seeing this behavior. I'm on a 2017 iMac. Booted into safe mode to no result.
 
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niji

Contributor
Feb 9, 2003
1,834
1,870
tokyo
hi

i am having the same thing happen to me.

i am convinced it is related to the Dynamic desktop.

if Dynamic desktop is not turned on, then i do not experience this.
with Dynamic desktop turned on, it always happens.

my machine:
Model Name: MacBook Air
Model Identifier: MacBookAir7,2
Processor Name: Intel Core i7
Processor Speed: 2.2 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache (per Core): 256 KB
L3 Cache: 4 MB
Memory: 8 GB
Boot ROM Version: MBA71.0178.B00
SMC Version (system): 2.27f2

as kernal panics go, its only a brief (very short time required being needed to reset itself) one.
but it is annoying.

my time zone is set to Automatic.
and i have tried to ensure that all possibly meaningful permissions are given to any possible Location info being required.
I'm wondering if its a problem of the startup sequence not getting its needed / expected info for timezone and / or actual current time, quick enough during the boot up process and then causing this temporary crash.
 
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Venderious

macrumors regular
Original poster
Dec 15, 2014
125
77
Groningen
hi

i am having the same thing happen to me.

i am convinced it is related to the Dynamic desktop.

if Dynamic desktop is not turned on, then i do not experience this.
with Dynamic desktop turned on, it always happens.

my machine:
Model Name: MacBook Air
Model Identifier: MacBookAir7,2
Processor Name: Intel Core i7
Processor Speed: 2.2 GHz
Number of Processors: 1
Total Number of Cores: 2
L2 Cache (per Core): 256 KB
L3 Cache: 4 MB
Memory: 8 GB
Boot ROM Version: MBA71.0178.B00
SMC Version (system): 2.27f2

as kernal panics go, its only a brief (very short time required being needed to reset itself) one.
but it is annoying.

my time zone is set to Automatic.
and i have tried to ensure that all possibly meaningful permissions are given to any possible Location info being required.
I'm wondering if its a problem of the startup sequence not getting its needed / expected info for timezone and / or actual current time, quick enough during the boot up process and then causing this temporary crash.

i do have my Region set to the USA, but use my local timezone time here in Japan.
i have no idea if that's involved or not.
I'm not sure whether this is linked to dynamic desktop. I did set my wallpaper to a dynamic desktop shortly after updating, but changed it after. The issue still persists. However, I've always found that the login screens on mac computers have many issues with bugs.
 

EdwardC

macrumors 6502
Jun 3, 2012
282
187
Georgia
Same issue here on a late '13 iMac as well as a 2012 mini. Dynamic on the mini only, same problem with both. Fire vault is off.
 

Khaleal

macrumors regular
Aug 24, 2013
185
75
I do have FileVault turned on.
Mojave has an issue where during boot, the screen will go black for a second and then come back and continue booting, since you have FileVault, you're prompted to login before the OS boots, and that's why you experience the black screen after "login"
 

Venderious

macrumors regular
Original poster
Dec 15, 2014
125
77
Groningen
Mojave has an issue where during boot, the screen will go black for a second and then come back and continue booting, since you have FileVault, you're prompted to login before the OS boots, and that's why you experience the black screen after "login"
That could indeed be the case. A few student in my university are experiencing the same issue, they all have filevault turned on as well.
 

Dc2006ster

macrumors regular
Jun 9, 2011
215
45
Alberta, Canada
I also have this issue. do not have FileVault on and use auto login so I do not have to login at startup.

The duration and of the black out is shorter if I do not have external drives turned on. When the drives are turned on there is activity on those drives during the blackout. Also, I removed third party ram in order to try and identify the cause of kernel panics that occurred even with high Sierra and this also shortened the black out time.

The behaviour is not predictable. This morning the blackout was very short and occurred at a different point in the progress bar and overall the startup was much slower than usual.
 
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Marcopolo53

macrumors regular
Oct 21, 2016
123
19
Toronto
Mojave has an issue where during boot, the screen will go black for a second and then come back and continue booting, since you have FileVault, you're prompted to login before the OS boots, and that's why you experience the black screen after "login"
Have same issue during the boot up process. Screen goes black for 1 sec then resumes boot up to eventual Login screen. This happens on late 2012 iMac and early 2016 Retina MacBook. Do not have FileVault enabled on either machine. Had similar black out resume loading on early HS 10.13.1, 10.13.2 and 10.13.3. Only fixed on 10.13.4 or maybe 10.13.3 Supplemental
 

Smoothie

macrumors 6502a
Jun 23, 2007
615
341
California
Same with FileVault on. It also behaves the same with or without dynamic desktop.

But I had a more serious issue just now. My 2017 iMac wouldn't come out of sleep mode. It's never failed to do this in the year I've had it. I had to hold down the power button for awhile until it rebooted. There were no external drives attached and nothing has changed on this iMac other than installing Mojave.
 

Tommy c

macrumors 6502
Sep 9, 2012
344
212
Pocono PA
Are we talking about when you turn on the computer, it has a blackish screen, then goes to boot mode with apple logo? Mine always started right up as soon as I hit the power button. Now it seems to go to this blackish screen then to the apple logo to boot up.
 

ericthered926

macrumors newbie
Jun 11, 2017
29
26
Yeah, the black screen is ugly, and the wallpaper on the lock screen is slightly pixelated as well... these are all very minor issues, but they do make the OS feel less polished.
 
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Marcopolo53

macrumors regular
Oct 21, 2016
123
19
Toronto
Just upgraded to 10.14.1 and there were EFI ROM updates included for both machines. Now, from a cold boot, no longer getting the load, wink to black and back to loading process. Guessing Apple has fine tuned the macOS plus EFI ROM together has eliminated the wink issue.
Nice job Apple
 
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