Hey!
I secretly updated spine on my other partition to look at the new features and while doing so I tried to stop an animation by setting speed to zero in the preview box from setup mode, after changing animation a couple times spine crashed.
here's the log:

Spine Launcher 3.5.21
Windows 10 Education x86 6.2
Java 1.7.0_80 Esoteric Software
32-bit Server VM
Updating to: Spine 3.6.35
Update complete.
Spine 3.6.35 Professional
Intel
Intel(R) HD Graphics 4600
4.3.0 - Build 20.19.15.4531
New hotkeys are available:
Mesh Tools View: Alt+E
Preview View: Alt+R
Auto Scroll: Ctrl+Slash
Scroll To Selected: Slash
Show All Bones/Slots: Ctrl+H
Main Menu: Alt+F
Next Skin: Period
Previous Skin: Comma
New Clipping: <not mapped>
Started.
Sorry, an unexpected error has occurred:
java.lang.NullPointerException
   at JF.a(SourceFile:619)
   at JP.a(SourceFile:555)
   at gD.a(SourceFile:28)
   at eM.a(SourceFile:182)
   at eM.a(SourceFile:147)
   at com.badlogic.gdx.scenes.scene2d.ui.Button.b(SourceFile:124)
   at com.badlogic.gdx.scenes.scene2d.ui.Button.d(SourceFile:114)
   at JQ.a(SourceFile:573)
   at gD.a(SourceFile:28)
   at eM.a(SourceFile:182)
   at eM.a(SourceFile:147)
   at com.badlogic.gdx.scenes.scene2d.ui.Button.b(SourceFile:124)
   at fo.a(SourceFile:92)
   at gF.a(SourceFile:89)
   at eS.a(SourceFile:59)
   at eU.b(SourceFile:351)
   at p.b(SourceFile:96)
   at az.a(SourceFile:332)
   at al.run(SourceFile:238)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:312)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:745)
   at java.awt.EventQueue.access$300(EventQueue.java:103)
   at java.awt.EventQueue$3.run(EventQueue.java:706)
   at java.awt.EventQueue$3.run(EventQueue.java:704)
   at java.security.AccessController.doPrivileged(Native Method)
   at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:715)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)

Oh nice I saw the new hotkeys in the log now, lol