Starting Safari Technology Preview (STP) Release 116 (Safari 14.1, WebKit 16611.1.5.3) automatically starts Safari Version 14.0.1 (16610.2.11.51.8).

This started happening on Catalina and continues after my upgrade to Big Sur.

Interestingly, if I start STP (and Safari 14.1 automatically starts right behind it) - once I close STP, and restart STP, STP becomes unresponsive.
The application loads, but I am unable to enter anything into the url location.  If I click on STP (to bring the app to the front), it is replaced 
by (or covered over by) Safari 14.1. 

Here are some errors from system.log

Nov 28 14:12:38 Cuchulainn Safari Technology Preview[18992]: getattrlist failed for /System/Library/Extensions/AppleIntelKBLGraphicsGLDriver.bundle/Contents/MacOS/AppleIntelKBLGraphicsGLDriver: #2: No such file or directory
Nov 28 14:12:38 Cuchulainn Safari Technology Preview[18992]: getattrlist failed for /Library/GPUBundles/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:12:38 Cuchulainn Safari Technology Preview[18992]: getattrlist failed for /System/Library/Extensions/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:12:38 Cuchulainn Safari Technology Preview[18992]: getattrlist failed for /System/Library/Frameworks/OpenGL.framework/Resources//GLRendererFloat.bundle/GLRendererFloat: #2: No such file or directory
Nov 28 14:12:40 Cuchulainn Safari Technology Preview[18992]: objc[18992]: Class AMSupportURLConnectionDelegate is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14800) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x1246988c0). One of the two will be used. Which one is undefined.
Nov 28 14:12:40 Cuchulainn Safari Technology Preview[18992]: objc[18992]: Class AMSupportURLSession is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14850) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x124698910). One of the two will be used. Which one is undefined.
Nov 28 14:12:41 Cuchulainn Safari[19009]: getattrlist failed for /System/Library/Extensions/AppleIntelKBLGraphicsGLDriver.bundle/Contents/MacOS/AppleIntelKBLGraphicsGLDriver: #2: No such file or directory
Nov 28 14:12:41 Cuchulainn Safari[19009]: getattrlist failed for /Library/GPUBundles/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:12:41 Cuchulainn Safari[19009]: getattrlist failed for /System/Library/Extensions/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:12:41 Cuchulainn Safari[19009]: getattrlist failed for /System/Library/Frameworks/OpenGL.framework/Resources//GLRendererFloat.bundle/GLRendererFloat: #2: No such file or directory
Nov 28 14:12:42 Cuchulainn com.apple.xpc.launchd[1] (com.apple.xpc.launchd.domain.user.501): Service "com.apple.xpc.launchd.unmanaged.LastPassSafari.19017" tried to register for endpoint "N24REP3BMN.lmi.lastpass.group.SafariExtensionPort.0" already registered by owner: com.apple.xpc.launchd.unmanaged.LastPassSafari.18998
Nov 28 14:12:42 Cuchulainn Safari[19009]: objc[19009]: Class AMSupportURLConnectionDelegate is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14800) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x1215b68c0). One of the two will be used. Which one is undefined.
Nov 28 14:12:42 Cuchulainn Safari[19009]: objc[19009]: Class AMSupportURLSession is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14850) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x1215b6910). One of the two will be used. Which one is undefined.
Nov 28 14:21:14 Cuchulainn com.apple.xpc.launchd[1] (com.apple.SafariTechnologyPreview.SandboxBroker[19002]): Service exited due to SIGKILL | sent by com.apple.SafariTechnologyPrevie[19002]
Nov 28 14:21:16 Cuchulainn com.apple.xpc.launchd[1]: Coalition Cache Hit: app<application.com.apple.SafariTechnologyPreview.221619199.221620358(501)> [3865]
Nov 28 14:21:16 Cuchulainn Safari Technology Preview[19996]: getattrlist failed for /System/Library/Extensions/AppleIntelKBLGraphicsGLDriver.bundle/Contents/MacOS/AppleIntelKBLGraphicsGLDriver: #2: No such file or directory
Nov 28 14:21:16 Cuchulainn Safari Technology Preview[19996]: getattrlist failed for /Library/GPUBundles/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:21:16 Cuchulainn Safari Technology Preview[19996]: getattrlist failed for /System/Library/Extensions/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:21:16 Cuchulainn Safari Technology Preview[19996]: getattrlist failed for /System/Library/Frameworks/OpenGL.framework/Resources//GLRendererFloat.bundle/GLRendererFloat: #2: No such file or directory
Nov 28 14:21:17 Cuchulainn Safari Technology Preview[19996]: objc[19996]: Class AMSupportURLConnectionDelegate is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14800) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x12572e8c0). One of the two will be used. Which one is undefined.
Nov 28 14:21:17 Cuchulainn Safari Technology Preview[19996]: objc[19996]: Class AMSupportURLSession is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14850) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x12572e910). One of the two will be used. Which one is undefined.
Nov 28 14:21:55 Cuchulainn com.apple.xpc.launchd[1]: Coalition Cache Hit: app<application.com.apple.Safari.221589318.221589325(501)> [3872]
Nov 28 14:21:55 Cuchulainn Safari[20017]: getattrlist failed for /System/Library/Extensions/AppleIntelKBLGraphicsGLDriver.bundle/Contents/MacOS/AppleIntelKBLGraphicsGLDriver: #2: No such file or directory
Nov 28 14:21:55 Cuchulainn Safari[20017]: getattrlist failed for /Library/GPUBundles/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:21:55 Cuchulainn Safari[20017]: getattrlist failed for /System/Library/Extensions/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:21:55 Cuchulainn Safari[20017]: getattrlist failed for /System/Library/Frameworks/OpenGL.framework/Resources//GLRendererFloat.bundle/GLRendererFloat: #2: No such file or directory
Nov 28 14:21:56 Cuchulainn Safari[20017]: objc[20017]: Class AMSupportURLConnectionDelegate is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14800) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x11e91a8c0). One of the two will be used. Which one is undefined.
Nov 28 14:21:56 Cuchulainn Safari[20017]: objc[20017]: Class AMSupportURLSession is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14850) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x11e91a910). One of the two will be used. Which one is undefined.
Nov 28 14:22:01 Cuchulainn com.apple.xpc.launchd[1] (com.apple.SafariServices.ExtensionHelper[20023]): Service exited due to SIGKILL | sent by com.apple.SafariServices.Extensi[20023]
Nov 28 14:24:59 Cuchulainn com.apple.xpc.launchd[1] (com.apple.xpc.launchd.domain.pid.deleted.1637): Service "com.apple.SafariTechnologyPreview.CacheDeleteExtension" tried to register for endpoint "com.apple.Safari.CacheDeleteExtension" already registered by owner: com.apple.Safari.CacheDeleteExtension
Nov 28 14:25:37 Cuchulainn Safari Technology Preview[22839]: getattrlist failed for /System/Library/Extensions/AppleIntelKBLGraphicsGLDriver.bundle/Contents/MacOS/AppleIntelKBLGraphicsGLDriver: #2: No such file or directory
Nov 28 14:25:37 Cuchulainn Safari Technology Preview[22839]: getattrlist failed for /Library/GPUBundles/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:25:37 Cuchulainn Safari Technology Preview[22839]: getattrlist failed for /System/Library/Extensions/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:25:37 Cuchulainn Safari Technology Preview[22839]: getattrlist failed for /System/Library/Frameworks/OpenGL.framework/Resources//GLRendererFloat.bundle/GLRendererFloat: #2: No such file or directory
Nov 28 14:25:38 Cuchulainn Safari Technology Preview[22839]: objc[22839]: Class AMSupportURLConnectionDelegate is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14800) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x11dbfa8c0). One of the two will be used. Which one is undefined.
Nov 28 14:25:38 Cuchulainn Safari Technology Preview[22839]: objc[22839]: Class AMSupportURLSession is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14850) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x11dbfa910). One of the two will be used. Which one is undefined.
Nov 28 14:25:39 Cuchulainn com.apple.xpc.launchd[1]: Coalition Cache Hit: app<application.com.apple.Safari.221589318.221589325(501)> [3872]
Nov 28 14:25:39 Cuchulainn Safari[22856]: getattrlist failed for /System/Library/Extensions/AppleIntelKBLGraphicsGLDriver.bundle/Contents/MacOS/AppleIntelKBLGraphicsGLDriver: #2: No such file or directory
Nov 28 14:25:39 Cuchulainn Safari[22856]: getattrlist failed for /Library/GPUBundles/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:25:39 Cuchulainn Safari[22856]: getattrlist failed for /System/Library/Extensions/AMDRadeonX6000GLDriver.bundle/Contents/MacOS/ATIRadeonX6000SCLib.dylib: #2: No such file or directory
Nov 28 14:25:39 Cuchulainn Safari[22856]: getattrlist failed for /System/Library/Frameworks/OpenGL.framework/Resources//GLRendererFloat.bundle/GLRendererFloat: #2: No such file or directory
Nov 28 14:25:40 Cuchulainn com.apple.xpc.launchd[1] (com.apple.xpc.launchd.domain.user.501): Service "com.apple.xpc.launchd.unmanaged.LastPassSafari.22861" tried to register for endpoint "N24REP3BMN.lmi.lastpass.group.SafariExtensionPort.0" already registered by owner: com.apple.xpc.launchd.unmanaged.LastPassSafari.22844
Nov 28 14:25:40 Cuchulainn Safari[22856]: objc[22856]: Class AMSupportURLConnectionDelegate is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14800) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x12033c8c0). One of the two will be used. Which one is undefined.
Nov 28 14:25:40 Cuchulainn Safari[22856]: objc[22856]: Class AMSupportURLSession is implemented in both /usr/lib/libauthinstall.dylib (0x7fff8ac14850) and /Library/Apple/System/Library/PrivateFrameworks/MobileDevice.framework/Versions/A/MobileDevice (0x12033c910). One of the two will be used. Which one is undefined.