Exception when reopening included file saved in separate window

[brandesNW]

1. Open a model with an included file
2. Go to the Code tab.
3. Click checkbox to open Code Tab in separate window.
4. Open a tab for an included file.
5. Make changes in the file buffer.
6. Close the separate window (on MacOS click the upper left-hand red button)

An exception occurs

Truncated stack trace:
java.lang.IndexOutOfBoundsException: Index -1 out of bounds for length 3
at java.base/jdk.internal.util.Preconditions.outOfBounds(Unknown Source)
at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Unknown Source)
at java.base/jdk.internal.util.Preconditions.checkIndex(Unknown Source)
at java.base/java.util.Objects.checkIndex(Unknown Source)
at java.base/java.util.ArrayList.get(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.setForegroundAt(Unknown Source)
at org.nlogo.app.Tabs.clearForeground$1(Tabs.scala:204)
at org.nlogo.app.Tabs.$anonfun$handle$4(Tabs.scala:209)
at org.nlogo.app.Tabs.$anonfun$handle$4$adapted(Tabs.scala:209)
at scala.collection.mutable.HashSet.foreach(HashSet.scala:79)
at org.nlogo.app.Tabs.forAllCodeTabs(Tabs.scala:328)
at org.nlogo.app.Tabs.clearErrors$1(Tabs.scala:209)
at org.nlogo.app.Tabs.handle(Tabs.scala:233)
at org.nlogo.window.Events$CompiledEvent.beHandledBy(Events.java:223)
at org.nlogo.window.Event.doRaise(Event.java:206)
at org.nlogo.window.Event.raise(Event.java:122)
at org.nlogo.window.CompilerManager$.$anonfun$$lessinit$greater$default$4$1(CompilerManager.scala:20)
at org.nlogo.window.CompilerManager$.$anonfun$$lessinit$greater$default$4$1$adapted(CompilerManager.scala:20)
at org.nlogo.window.CompilerManager.raiseEvent(CompilerManager.scala:34)
at org.nlogo.window.CompilerManager.compileProcedures(CompilerManager.scala:221)
at org.nlogo.window.CompilerManager.compileAll(CompilerManager.scala:173)
at org.nlogo.window.CompilerManager.handle(CompilerManager.scala:137)
at org.nlogo.window.Events$CompileAllEvent.beHandledBy(Events.java:185)
at org.nlogo.window.Event.doRaise(Event.java:206)
at org.nlogo.window.Event.raise(Event.java:122)
at org.nlogo.app.codetab.CodeTab.compile(CodeTab.scala:163)
at org.nlogo.app.codetab.CodeTab.handle(CodeTab.scala:144)
at org.nlogo.app.codetab.TemporaryCodeTab.handle(TemporaryCodeTab.scala:130)
at org.nlogo.app.common.Events$SwitchedTabsEvent.beHandledBy(Events.java:41)
at org.nlogo.window.Event.doRaise(Event.java:206)
at org.nlogo.window.Event.raise(Event.java:122)
at org.nlogo.app.CodeTabsPanel.stateChanged(CodeTabsPanel.scala:105)
at java.desktop/javax.swing.JTabbedPane.fireStateChanged(Unknown Source)
at java.desktop/javax.swing.JTabbedPane$ModelListener.stateChanged(Unknown Source)
at java.desktop/javax.swing.DefaultSingleSelectionModel.fireStateChanged(Unknown Source)
at java.desktop/javax.swing.DefaultSingleSelectionModel.setSelectedIndex(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.setSelectedIndexImpl(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.removeTabAt(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.remove(Unknown Source)
at java.desktop/java.awt.Container.addImpl(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.insertTab(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.addTab(Unknown Source)
at java.desktop/javax.swing.JTabbedPane.add(Unknown Source)
at org.nlogo.app.AppTabManager.$anonfun$switchToNoSeparateCodeWindow$1(AppTabManager.scala:258)
at org.nlogo.app.AppTabManager.$anonfun$switchToNoSeparateCodeWindow$1$adapted(AppTabManager.scala:257)
at scala.collection.immutable.Range.foreach(Range.scala:158)
at org.nlogo.app.AppTabManager.switchToNoSeparateCodeWindow(AppTabManager.scala:257)
at org.nlogo.app.CodeTabsPanel$$anon$2.windowClosing(CodeTabsPanel.scala:86)

[LaCuneta]

This looks like slightly different steps to produce #2104