[macOS] Lightroom Classic 15.3 intermittently hangs; after Force Quit it can no longer open RAW files, while 15.2.1 works

Forum|Forum|1 month ago
April 20, 2026
3 replies
145 views

Issue summary
On my Mac, Lightroom Classic 15.3 becomes unresponsive after some period of normal use. I have to Force Quit it. After that, Lightroom Classic can relaunch, but RAW files can no longer be opened properly. I cannot guarantee exact reproduction steps every time, but the issue has happened multiple times in 15.3 and has not happened for me in 15.2.1 on the same machine.

Environment
- Lightroom Classic: 15.3
- macOS: 26.4.1
- Apple Silicon Mac: M1 Max

What I can confirm
- This issue started after updating to 15.3.
- It happens after some time of normal RAW workflow use, not immediately on launch.
- Once Lightroom hangs, I have to Force Quit it.
- After relaunch, RAW files still cannot be opened properly.
- Downgrading to 15.2.1 on the same Mac resolves the issue.

Relevant lines from the report:

Process: Adobe Lightroom Classic [12526]
Version: 15.3
OS Version: Mac OS X 26.4.1 (25E253)
Exception Type: EXC_CRASH (SIGTERM)
Signal Number: 15
Publisher Process Name: pkill

Thread 62:
0 AdobeCrashReporter _callstack_signal_handler(int, __siginfo*, void*) + 60
1 libsystem_platform.dylib _sigtramp + 56
2 ??? 0x0000000901c651d0 0x0 + 38684479952
3 CameraRaw AgCoreGraphicsOGL_load + 17439284
4 CameraRaw AgCoreGraphicsOGL_load + 8547028
5 CameraRaw AgCoreGraphicsOGL_load + 5852652
6 libdispatch.dylib _dispatch_client_callout2 + 16
7 libdispatch.dylib _dispatch_apply_invoke3 + 336
8 libdispatch.dylib _dispatch_client_callout + 16
9 libdispatch.dylib _dispatch_once_callout + 32
10 libdispatch.dylib _dispatch_apply_invoke_and_wait + 364
11 libdispatch.dylib _dispatch_apply_with_attr_f + 1312
12 CameraRaw AgCoreGraphicsOGL_load + 5852900
13 CameraRaw AgCoreGraphicsOGL_load + 8542352
14 CameraRaw AgCoreGraphicsOGL_load + 17442892
15 CameraRaw AgCoreGraphicsOGL_load + 8658680
16 CameraRaw AgCoreGraphicsOGL_load + 17492120
17 CameraRaw AgCoreGraphicsOGL_load + 9852988
18 CameraRaw AgCoreGraphicsOGL_load + 6204072
19 CameraRaw private_load_Utilities + 96316

com.adobe.GPUFoundation.framework
VulcanMessage5.dylib
VulcanControl.dylib
com.adobe.ag.AgImageIO ... /CameraRaw.lrtoolkit/Versions/A/CameraRaw
com.adobe.ag.vulcan ... /Vulcan.agtoolkit/Contents/MacOS/Vulcan

Sameer K

Community Manager

Hey, @daring_Ripple98BC & @iJoyer. Welcome to the Lightroom Classic Community. I'll help you figure this out.]Please share the system info from Lightroom Classic from Help > System info > Copy and paste into a text document > Upload and attach here.

Where do you keep your Lightroom Classic catalog? Does the delay occur randomly, or after you've applied specific edits, or a number of edits, to the image, such as Lens Corrections, Denoise, and Masks?

As primary steps, try this:

Reset Lightroom by holding the OPT + SHIFT when you launch Lightroom and select 'Yes'.
Ensure Lightroom Classic has the required permissions on macOS: https://adobe.ly/3DyUwsz
Go to the following location to launch Lightroom via the terminal.
In Finder > Application Folder > Open Lightroom Classic Folder > Right-click on Lightroom .app > Show Package Contents > Contents > macOS > Lightroom—double-click to open.

Share the log of what you see in the terminal window when Lightroom Launches.

Let me know how it goes.

Thanks!
Sameer K

(Type '@' and type my name to mention me when you reply)