After around 1500 vertices placed on an image, it has a random chance of crashing with this error log:
Note: I'm also using multiple constraints, with the image weighted.

I checked the Forum and didn't come across this problem, I had a similar problem before the 3.7 update -

Spine Launcher 3.7.81
Esoteric Software LLC (C) 2013-2019
Windows 10 Home x86 10.0
Up to date: Spine 3.7.87
Spine 3.7.87 Professional
Licensed to: ****
NVIDIA Corporation
GeForce GTX 1080/PCIe/SSE2
4.6.0 NVIDIA 416.94
OpenAL 1.1, Default audio device Started.

Sorry, an unexpected error has occurred:
java.lang.RuntimeException: java.lang.OutOfMemoryError: Java heap space
at nt.a(SourceFile:364)
at av.a(SourceFile:75)
at ap.run(SourceFile:271)
at java.desktop/java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.desktop/java.awt.EventQueue.access$600(Unknown Source)
at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.desktop/java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.run(Unknown Source)
Caused by: java.lang.OutOfMemoryError: Java heap space
at iv.c(SourceFile:305)
at iv.b(SourceFile:299)
at GT.a(SourceFile:113)
at Go.d(SourceFile:132)
at Gh.d(SourceFile:271)
at Iy.a(SourceFile:147)
at HV.a(SourceFile:53)
at Iy.a(SourceFile:99)
at HV.a(SourceFile:78)
at uo.a(SourceFile:60)
at HY.a(SourceFile:128)
at java.base/java.lang.invoke.LambdaForm$DMH/12676424.invokeVirtual(LambdaForm$DMH)
at java.base/java.lang.invoke.LambdaForm$MH/29472806.invoke(LambdaForm$MH)
at java.base/java.lang.invoke.LambdaForm$MH/10697531.linkToTargetMethod(LambdaForm$MH)
at nd.b(SourceFile:331)
at dY.b(SourceFile:209)
at ne.b(SourceFile:363)
at dY.b(SourceFile:183)
at q.b(SourceFile:124)
at q.b(SourceFile:124)
at aD.a(SourceFile:344)
at ap.run(SourceFile:259)
at java.desktop/java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.desktop/java.awt.EventQueue.access$600(Unknown Source)
at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
at java.desktop/java.awt.EventQueue$4.run(Unknown Source)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.desktop/java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)