P: crashes on export of JPEG's

Excellent.  I don't think the new platform has a way to indicate a bug has been "acknowledged", as the old one did?

John we do have a bug open for this and should have a fix in a future update. 

The Community forum has numerous reports in the last couple months of crashes during export:

https://community.adobe.com/t5/lightroom-classic/lightroom-crash-report-exporting/m-p/11452466?page=1

https://community.adobe.com/t5/lightroom-classic/lr-9-4-crashing-during-export/m-p/11450583?page=1

https://community.adobe.com/t5/lightroom-classic/lrc-can-not-export-photos/m-p/11387295?page=1

https://community.adobe.com/t5/lightroom-classic/lightroom-classic-unexpectedly-quits-on-export-makes-me-sign-in/m-p/11369490?page=1

https://community.adobe.com/t5/lightroom-classic/lightroom-crashing-while-exporting/m-p/11351659?page=1

https://community.adobe.com/t5/lightroom-classic/lightroom-locking-up-and-crashing/m-p/11297484?page=1

https://community.adobe.com/t5/lightroom-classic/no-longer-can-export-jpeg-images-without-lrc-crashing/m-p/11287878?page=1

https://community.adobe.com/t5/lightroom-classic/constant-crashing-while-exporting-raf-to-jpeg/m-p/11287244?page=1

Does this shed any light?

Process:               Adobe Lightroom Classic [1161]

Path:                  /Applications/Adobe Lightroom Classic/Adobe Lightroom Classic.app/Contents/MacOS/Adobe Lightroom Classic

Identifier:            com.adobe.LightroomClassicCC7

Version:               9.4 [202008061458-dbb2971e] (9.4)

Code Type:             X86-64 (Native)

Parent Process:        ??? [1]

Responsible:           Adobe Lightroom Classic [1161]

User ID:               501

Date/Time:             2020-09-22 16:21:14.883 +0100

OS Version:            Mac OS X 10.15.6 (19G2021)

Report Version:        12

Bridge OS Version:     3.0 (14Y908)

Anonymous UUID:        D660F80B-B5D0-8B24-79FA-DA06D27222C6

Time Awake Since Boot: 700 seconds

System Integrity Protection: enabled

Crashed Thread:        0  Dispatch queue: com.apple.main-thread

Exception Type:        EXC_BAD_ACCESS (SIGSEGV)

Exception Codes:       EXC_I386_GPFLT

Exception Note:        EXC_CORPSE_NOTIFY

Termination Signal:    Segmentation fault: 11

Termination Reason:    Namespace SIGNAL, Code 0xb

Terminating Process:   exc handler [1161]

Thread 0 Crashed:: Dispatch queue: com.apple.main-thread

0   com.apple.CoreFoundation       0x00007fff3866c859 __CFRunLoopInsertionIndexInTimerArray + 27

1   ???                           000000000000000000 0 + 0

2   com.apple.CoreFoundation       0x00007fff3866c7f7 __CFRepositionTimerInMode + 109

3   com.apple.CoreFoundation       0x00007fff386be6c2 __CFRunLoopDoTimer + 1726

4   com.apple.CoreFoundation       0x00007fff386bde47 __CFRunLoopDoTimers + 322

5   com.apple.CoreFoundation       0x00007fff386a2bea __CFRunLoopRun + 1871

6   com.apple.CoreFoundation       0x00007fff386a1e3e CFRunLoopRunSpecific + 462

7   com.apple.HIToolbox           0x00007fff372ceabd RunCurrentEventLoopInMode + 292

8   com.apple.HIToolbox           0x00007fff372ce7d5 ReceiveNextEventCommon + 584

9   com.apple.HIToolbox           0x00007fff372ce579 _BlockUntilNextEventMatchingListInModeWithFilter + 64

10  com.apple.AppKit               0x00007fff35914039 _DPSNextEvent + 883

11  com.apple.AppKit               0x00007fff35912880 -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 1352

12  com.apple.AppKit               0x00007fff3590458e -[NSApplication run] + 658

13  com.apple.AppKit               0x00007fff358d6396 NSApplicationMain + 777

14  com.adobe.LightroomClassicCC7 0x00000001030ef33a main + 1546

15  libdyld.dylib                 0x00007fff72710cc9 start + 1

Thread 1:: Worker Thread Dispatcher

0   libsystem_kernel.dylib         0x00007fff72854882 __psynch_cvwait + 10

1   libsystem_pthread.dylib       0x00007fff72915425 _pthread_cond_wait + 698

2   com.adobe.ag.kernel           0x00000001035ea26f AgConditionLock_wait + 40

3   com.adobe.ag.kernel           0x00000001035d1e83 AgTransitQueue_dequeueToLuaState + 112

4   com.adobe.ag.kernel           0x00000001035d28d1 0x1035b1000 + 137425

5   com.adobe.ag.kernel           0x00000001035bb363 0x1035b1000 + 41827

6   com.adobe.ag.kernel           0x00000001035ca0c2 0x1035b1000 + 102594

7   com.adobe.ag.kernel           0x00000001035bb7a2 0x1035b1000 + 42914

8   com.adobe.ag.kernel           0x00000001035b35c7 lua_call + 39

9   com.adobe.ag.substrate         0x00000001037339cd AgLua_callWithAutoReleasePool + 76

10  com.adobe.ag.kernel           0x00000001035bb363 0x1035b1000 + 41827

11  com.adobe.ag.kernel           0x00000001035ca0c2 0x1035b1000 + 102594

12  com.adobe.ag.kernel           0x00000001035bb7a2 0x1035b1000 + 42914

13  com.adobe.ag.kernel           0x00000001035baebb 0x1035b1000 +

How come nothing else crashes it - other intensive apps e.g photoshop don’t crash

But how come nothing else crashes it? Other intensive apps don’t crash it 

"Sometimes it works fine. Sometimes it crashes and quits. Sometimes it crashes the whole computer."

This is some indication that you possibly have some hardware problem. Check your RAM memory and disk.

cheers John - now changed

Peter, I strongly recommend you edit your post to remove the email address. (Click the three dots at the top right of the post.)

Thanks!

Lightroom Classic version: 9.4 [ 202008061458-dbb2971e ]

License: Creative Cloud

Language setting: en-GB

Operating system: Mac OS 10

Version: 10.15.6 [19G2021]

Application architecture: x64

Logical processor count: 8

Processor speed: 2.9 GHz

SqLite Version: 3.30.1

Built-in memory: 16,384.0 MB

Real memory available to Lightroom: 16,384.0 MB

Real memory used by Lightroom: 501.4 MB (3.0%)

Virtual memory used by Lightroom: 5,796.3 MB

Memory cache size: 55.6MB

Internal Camera Raw version: 12.4 [ 555 ]

Maximum thread count used by Camera Raw: 5

Camera Raw SIMD optimization: SSE2,AVX,AVX2

Camera Raw virtual memory: 0MB / 8191MB (0%)

Camera Raw real memory: 0MB / 16384MB (0%)

Displays: 1) 3440x1440

Graphics Processor Info: 

Metal: AMD Radeon Pro 460

The battery was showing as needing a service, so I had it replaced. Also upgraded to latest OS Catalina - but no joy!