HTTP ERROR 500 java.lang.OutOfMemoryError: Java heap space

This is from the hub in my RV which only has a few devices connected:

I know I can fix it by rebooting, but just wanted to report it in case anyone else hits this. I know there's some focus on fixing stability /performance issues like this so I figured I'd post in case it's helpful.

If I try to access the root URL "/" I get a more detailed backtrace:

Caused by:

com.google.common.util.concurrent.ExecutionError: java.lang.OutOfMemoryError: Java heap space
	at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2049)
	at com.google.common.cache.LocalCache.get(LocalCache.java:3951)
	at com.google.common.cache.LocalCache$LocalManualCache.get(LocalCache.java:4871)
	at com.github.jknack.handlebars.cache.GuavaTemplateCache.get(GuavaTemplateCache.java:75)
	at com.github.jknack.handlebars.Handlebars.compile(Handlebars.java:414)
	at com.github.jknack.handlebars.Handlebars.compile(Handlebars.java:357)
	at com.github.jknack.handlebars.Handlebars.compile(Handlebars.java:343)
	at spark.template.handlebars.HandlebarsTemplateEngine.render(HandlebarsTemplateEngine.java:75)
	at spark.template.handlebars.HandlebarsTemplateEngine$render.call(Unknown Source)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:47)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:128)
	at com.hubitat.hub.route.BaseRoute.renderWithHeader(BaseRoute.groovy:50)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:98)
	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:325)
	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:352)
	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1034)
	at org.codehaus.groovy.runtime.callsite.PogoMetaClassSite.callCurrent(PogoMetaClassSite.java:68)
	at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallCurrent(CallSiteArray.java:51)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:157)
	at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:185)
	at com.hubitat.hub.route.GenericRoute$_configureRoutes_closure2.doCall(GenericRoute.groovy:67)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:98)
	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:325)
	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:264)
	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1034)
	at groovy.lang.Closure.call(Closure.java:420)
	at org.codehaus.groovy.runtime.ConvertedClosure.invokeCustom(ConvertedClosure.java:54)
	at org.codehaus.groovy.runtime.ConversionHandler.invoke(ConversionHandler.java:124)
	at com.sun.proxy.$Proxy24.handle(Unknown Source)
	at spark.RouteImpl$1.handle(RouteImpl.java:72)
	at spark.http.matching.Routes.execute(Routes.java:61)
	at spark.http.matching.MatcherFilter.doFilter(MatcherFilter.java:134)
	at spark.embeddedserver.jetty.JettyHandler.doHandle(JettyHandler.java:50)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1584)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
	at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:59)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:127)
	at org.eclipse.jetty.server.Server.handle(Server.java:501)
	at org.eclipse.jetty.server.HttpChannel.lambda$handle$1(HttpChannel.java:383)
	at org.eclipse.jetty.server.HttpChannel.dispatch(HttpChannel.java:556)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:375)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:273)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:311)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:105)
	at org.eclipse.jetty.io.ChannelEndPoint$1.run(ChannelEndPoint.java:104)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:336)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:313)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:171)
	at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:129)
	at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:375)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:806)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$Runner.run(QueuedThreadPool.java:938)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.OutOfMemoryError: Java heap space