Hi, here is my log - Thunderbird crashed repeatedly and cannot be started even in safe mode, on latest Mac OSX Big Sur, everything updated: AdapterDeviceID: 0x8a51 AdapterVendorID: 0x8086 Add-ons: %7Ba300a000-5e21-4ee0-a115-9ec8f4eaa92b%7D:0.5.2b4,largermessagelist%40pierrelebedel:1.0.0,largermessagelist%40royprins:0.0.1,default-theme%40mozilla.org:1.2,google%40search.mozilla.org:1.0,ddg%40search.mozilla.org:1.0,amazondotcom%40search.mozilla.org:1.1,wikipedia%40search.mozilla.org:1.0,bing%40search.mozilla.org:1.0 AvailablePhysicalMemory: 574238720 AvailableSwapMemory: 0 BuildID: 20210924213438 ContentSandboxCapable: 1 ContentSandboxLevel: 1 CrashTime: 1632932426 DOMIPCEnabled: 1 EventLoopNestingLevel: 1 FramePoisonBase: 9223372036600930304 FramePoisonSize: 4096 InstallTime: 1632863297 Notes: FP(D00-L1000-W00000000-T000) WR? WR+ OMTP? OMTP- GL Context? GL Context+ ProductID: {3550f703-e582-4d05-9a08-453d09bdfdc6} ProductName: Thunderbird PurgeablePhysicalMemory: 644698112 ReleaseChannel: release SafeMode: 0 SecondsSinceLastCrash: 217 StartupCrash: 0 StartupTime: 1632932418 TelemetryEnvironment: {"build":{"applicationId":"{3550f703-e582-4d05-9a08-453d09bdfdc6}","applicationName":"Thunderbird","architecture":"x86-64","buildId":"20210924213438","version":"91.1.2","vendor":null,"displayVersion":"91.1.2","platformVersion":"91.1.0","xpcomAbi":"x86_64-gcc3","updaterAvailable":true},"partner":{"distributionId":null,"distributionVersion":null,"partnerId":null,"distributor":null,"distributorChannel":null,"partnerNames":[]},"system":{"memoryMB":16384,"virtualMaxMB":null,"cpu":{"extensions":["hasMMX","hasSSE","hasSSE2","hasSSE3","hasSSSE3","hasSSE4_1","hasSSE4_2","hasAVX","hasAVX2","hasAES"]},"os":{"name":"Darwin","version":"20.6.0","locale":"en-US"},"hdd":{"profile":{"model":null,"revision":null,"type":null},"binary":{"model":null,"revision":null,"type":null},"system":{"model":null,"revision":null,"type":null}},"gfx":{"D2DEnabled":null,"DWriteEnabled":null,"ContentBackend":"Skia","Headless":false,"EmbeddedInFirefoxReality":null,"adapters":[{"description":null,"vendorID":"0x8086","deviceID":"0x8a51","subsysID":null,"RAM":0,"driver":null,"driverVendor":null,"driverVersion":null,"driverDate":null,"GPUActive":true}],"monitors":[{"screenWidth":1440,"screenHeight":900,"scale":2}],"features":{"compositor":"none","hwCompositing":{"status":"available"},"gpuProcess":{"status":"unused"},"wrQualified":{"status":"available"},"webrender":{"status":"available"},"wrCompositor":{"status":"available"},"wrSoftware":{"status":"available"},"openglCompositing":{"status":"available"},"omtp":{"status":"disabled:FEATURE_FAILURE_DISABLED"}}},"appleModelId":"MacBookAir9,1"},"settings":{"blocklistEnabled":true,"e10sEnabled":true,"e10sMultiProcesses":8,"fissionEnabled":false,"telemetryEnabled":false,"locale":"en-US","intl":{},"update":{"channel":"release","enabled":true},"userPrefs":{"browser.search.region":"US","layout.css.devPixelsPerPx":"-2","widget.content.allow-gtk-dark-theme":false,"widget.content.gtk-high-contrast.enabled":true},"sandbox":{"effectiveContentProcessLevel":1,"contentWin32kLockdownState":3},"addonCompatibilityCheckEnabled":true,"isDefaultBrowser":null},"profile":{}} ThreadIdNameMapping: 6:"IPC I/O Parent",8:"StreamTrans #2",9:"Socket Thread",10:"Permission",11:"JS Watchdog",15:"TaskController Thread #2",20:"TaskController Thread #7",13:"TaskController Thread #0",17:"TaskController Thread #4",18:"TaskController Thread #5",16:"TaskController Thread #3",19:"TaskController Thread #6",14:"TaskController Thread #1",22:"Timer",23:"Cache2 I/O",24:"Cookie",25:"BackgroundThreadPool #1",26:"Worker Launcher",27:"Renderer",28:"WRWorker#0",33:"WRWorker#5",29:"WRWorker#1",31:"WRWorker#3",32:"WRWorker#4",36:"WRWorkerLP#0",30:"WRWorker#2",34:"WRWorker#6",37:"WRWorkerLP#1",41:"WRWorkerLP#5",39:"WRWorkerLP#3",40:"WRWorkerLP#4",35:"WRWorker#7",43:"WRWorkerLP#7",42:"WRWorkerLP#6",38:"WRWorkerLP#2",44:"Compositor",46:"ImageIO",47:"IPDL Background",49:"QuotaManager IO",51:"IndexedDB #1",52:"DOM Worker",53:"StreamTrans #8",53:"mozStorage #1",55:"TRR Background",56:"DNS Resolver #1",57:"StyleThread#0",60:"StyleThread#3",58:"StyleThread#1",59:"StyleThread#2",61:"StyleThread#4",62:"StyleThread#5",66:"ImageBridgeChld",67:"ProcessHangMon",68:"GMPThread",68:"WRSceneBuilderLP#1",69:"WRRenderBackend#1",67:"WRSceneBuilder#1",70:"BgIOThreadPool #1",72:"localStorage DB",73:"ExtensionProtocolHandler",74:"StreamTrans #18",76:"WRSceneBuilder#2",78:"WRRenderBackend#2",77:"WRSceneBuilderLP#2",85:"StreamTrans #26",82:"IMAP",83:"IMAP",84:"IMAP",85:"IMAP",86:"HTML5 Parser",87:"DOM Worker",88:"SSL Cert #1",89:"SSL Cert #2",90:"mozStorage #4",91:"mozStorage #5",93:"StreamTrans #29",92:"Font Loader", Throttleable: 1 TotalPhysicalMemory: 17179869184 URL: about:blank UptimeTS: 8.80572616 Version: 91.1.2 useragent_locale: en-US This report also contains technical information about the state of the application when it crashed.