Highly likely to be related to the problems sourceforge has been having recently, sometimes loading easyfax's data (at https://svn.code.sf.net/p/easyfax/code/Easyfax.xml) fails:
DynamicBotFetcher already catches a lot of errors, so maybe adding ConnectException to that would fix the debug error (though not the general failure).
Code:
Unexpected error, debug log printed.
class java.net.ConnectException: Connection timed out: connect
java.net.ConnectException: Connection timed out: connect
at java.base/java.net.PlainSocketImpl.connect0(Native Method)
at java.base/java.net.PlainSocketImpl.socketConnect(PlainSocketImpl.java:101)
at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399)
at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242)
at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224)
at java.base/java.net.Socket.connect(Socket.java:609)
at java.base/java.net.Socket.connect(Socket.java:558)
at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:182)
at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
at java.base/sun.net.www.http.HttpClient.<init>(HttpClient.java:242)
at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:341)
at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:362)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1248)
at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1187)
at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1081)
at java.base/sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:1015)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1587)
at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1515)
at java.base/java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:527)
at net.sourceforge.kolmafia.utilities.FileUtilities.getInputStreamFromConnection(FileUtilities.java:275)
at net.sourceforge.kolmafia.utilities.FileUtilities.downloadFile(FileUtilities.java:434)
at net.sourceforge.kolmafia.persistence.FaxBotDatabase$DynamicBotFetcher.run(FaxBotDatabase.java:477)
at net.sourceforge.kolmafia.RequestThread.postRequest(RequestThread.java:295)
at net.sourceforge.kolmafia.RequestThread.postRequest(RequestThread.java:280)
at net.sourceforge.kolmafia.persistence.FaxBotDatabase.configureFaxBot(FaxBotDatabase.java:153)
at net.sourceforge.kolmafia.persistence.FaxBotDatabase.configureFaxBots(FaxBotDatabase.java:140)
at net.sourceforge.kolmafia.persistence.FaxBotDatabase.configure(FaxBotDatabase.java:100)
at net.sourceforge.kolmafia.textui.RuntimeLibrary.faxbot(RuntimeLibrary.java:4679)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at net.sourceforge.kolmafia.textui.parsetree.LibraryFunction.execute(LibraryFunction.java:110)
at net.sourceforge.kolmafia.textui.parsetree.FunctionCall.execute(FunctionCall.java:161)
at net.sourceforge.kolmafia.textui.parsetree.BasicScope.execute(BasicScope.java:566)
at net.sourceforge.kolmafia.textui.parsetree.Conditional.execute(Conditional.java:97)
at net.sourceforge.kolmafia.textui.parsetree.If.execute(If.java:64)
at net.sourceforge.kolmafia.textui.parsetree.BasicScope.execute(BasicScope.java:566)
at net.sourceforge.kolmafia.textui.parsetree.UserDefinedFunction.execute(UserDefinedFunction.java:136)
at net.sourceforge.kolmafia.textui.AshRuntime.executeScope(AshRuntime.java:318)
at net.sourceforge.kolmafia.textui.AshRuntime.execute(AshRuntime.java:234)
at net.sourceforge.kolmafia.textui.AshRuntime.execute(AshRuntime.java:226)
at net.sourceforge.kolmafia.textui.command.CallScriptCommand.call(CallScriptCommand.java:264)
at net.sourceforge.kolmafia.textui.command.CallScriptCommand.run(CallScriptCommand.java:77)
at net.sourceforge.kolmafia.KoLmafiaCLI.doExecuteCommand(KoLmafiaCLI.java:593)
at net.sourceforge.kolmafia.KoLmafiaCLI.executeCommand(KoLmafiaCLI.java:546)
at net.sourceforge.kolmafia.KoLmafiaCLI.executeLine(KoLmafiaCLI.java:448)
at net.sourceforge.kolmafia.KoLmafiaCLI.executeLine(KoLmafiaCLI.java:316)
at net.sourceforge.kolmafia.swingui.CommandDisplayFrame$CommandQueueHandler.handleQueue(CommandDisplayFrame.java:198)
at net.sourceforge.kolmafia.swingui.CommandDisplayFrame$CommandQueueHandler.run(CommandDisplayFrame.java:168)
DynamicBotFetcher already catches a lot of errors, so maybe adding ConnectException to that would fix the debug error (though not the general failure).