diff --git a/icd-web-client/src/main/scala/icd/web/client/IcdWebClient.scala b/icd-web-client/src/main/scala/icd/web/client/IcdWebClient.scala
index 6c817585..dc9b63a5 100644
--- a/icd-web-client/src/main/scala/icd/web/client/IcdWebClient.scala
+++ b/icd-web-client/src/main/scala/icd/web/client/IcdWebClient.scala
@@ -203,8 +203,8 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
     if (saveHistory) {
       pushState(
         viewType = SelectView,
-        maybeSourceSubsystem = selectDialog.subsystem.getSubsystemWithVersion,
-        maybeTargetSubsystem = selectDialog.targetSubsystem.getSubsystemWithVersion,
+        maybeSourceSubsystem = selectDialog.subsystem.getSubsystemWithVersion(),
+        maybeTargetSubsystem = selectDialog.targetSubsystem.getSubsystemWithVersion(),
         maybeIcd = selectDialog.icdChooser.getSelectedIcdVersion
       )
     } else {
@@ -281,8 +281,8 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
    */
   private object ComponentLinkSelectionHandler extends ComponentListener {
     def componentSelected(link: ComponentLink): Unit = {
-      val maybeSv              = selectDialog.subsystem.getSubsystemWithVersion
-      val maybeTargetSv        = selectDialog.targetSubsystem.getSubsystemWithVersion
+      val maybeSv              = selectDialog.subsystem.getSubsystemWithVersion()
+      val maybeTargetSv        = selectDialog.targetSubsystem.getSubsystemWithVersion()
       val maybeSubsystem       = maybeSv.map(_.subsystem)
       val maybeTargetSubsystem = maybeTargetSv.map(_.subsystem)
 
@@ -495,8 +495,8 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
     if (saveHistory) {
       pushState(
         viewType = SelectView,
-        maybeSourceSubsystem = selectDialog.subsystem.getSubsystemWithVersion,
-        maybeTargetSubsystem = selectDialog.targetSubsystem.getSubsystemWithVersion,
+        maybeSourceSubsystem = selectDialog.subsystem.getSubsystemWithVersion(),
+        maybeTargetSubsystem = selectDialog.targetSubsystem.getSubsystemWithVersion(),
         maybeIcd = selectDialog.icdChooser.getSelectedIcdVersion
       )
     }
@@ -511,8 +511,8 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
       pushState(
         replace = false,
         viewType = ComponentView,
-        maybeSourceSubsystem = selectDialog.subsystem.getSubsystemWithVersion,
-        maybeTargetSubsystem = selectDialog.targetSubsystem.getSubsystemWithVersion,
+        maybeSourceSubsystem = selectDialog.subsystem.getSubsystemWithVersion(),
+        maybeTargetSubsystem = selectDialog.targetSubsystem.getSubsystemWithVersion(),
         maybeIcd = selectDialog.icdChooser.getSelectedIcdVersion,
         maybeUri = Some(uri)
       )
@@ -553,10 +553,10 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
     val maybeSv =
       if (currentView == StatusView)
         statusDialog.getSubsystemWithVersion
-      else selectDialog.subsystem.getSubsystemWithVersion
+      else selectDialog.subsystem.getSubsystemWithVersion()
 
     maybeSv.foreach { sv =>
-      val maybeTargetSv   = selectDialog.targetSubsystem.getSubsystemWithVersion
+      val maybeTargetSv   = selectDialog.targetSubsystem.getSubsystemWithVersion()
       val maybeIcdVersion = selectDialog.icdChooser.getSelectedIcdVersion.map(_.icdVersion)
       val searchAll       = selectDialog.searchAllSubsystems()
       val clientApi       = selectDialog.clientApi()
@@ -582,10 +582,10 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
     val maybeSv =
       if (currentView == StatusView)
         statusDialog.getSubsystemWithVersion
-      else selectDialog.subsystem.getSubsystemWithVersion
+      else selectDialog.subsystem.getSubsystemWithVersion()
 
     maybeSv.foreach { sv =>
-      val maybeTargetSv   = selectDialog.targetSubsystem.getSubsystemWithVersion
+      val maybeTargetSv   = selectDialog.targetSubsystem.getSubsystemWithVersion()
       val maybeIcdVersion = selectDialog.icdChooser.getSelectedIcdVersion.map(_.icdVersion)
       val uri             = ClientRoutes.makeGraph(sv, maybeTargetSv, maybeIcdVersion, options)
       dom.window.open(uri) // opens in new window or tab
@@ -597,7 +597,7 @@ case class IcdWebClient(csrfToken: String, inputDirSupported: Boolean) {
     val maybeSv =
       if (currentView == StatusView)
         statusDialog.getSubsystemWithVersion
-      else selectDialog.subsystem.getSubsystemWithVersion
+      else selectDialog.subsystem.getSubsystemWithVersion()
 
     val uri =
       if (maybeSv.isDefined)
diff --git a/icd-web-client/src/main/scala/icd/web/client/SelectDialog.scala b/icd-web-client/src/main/scala/icd/web/client/SelectDialog.scala
index fbe04545..76032386 100644
--- a/icd-web-client/src/main/scala/icd/web/client/SelectDialog.scala
+++ b/icd-web-client/src/main/scala/icd/web/client/SelectDialog.scala
@@ -91,7 +91,7 @@ case class SelectDialog(mainContent: MainContent, listener: SelectDialogListener
   }
 
   private def clientApiCheckboxChanged()(e: dom.Event): Unit = {
-    val maybeTargetSv = targetSubsystem.getSubsystemWithVersion
+    val maybeTargetSv = targetSubsystem.getSubsystemWithVersion()
     searchAllCheckbox.disabled = maybeTargetSv.isDefined || !clientApi()
   }
 
@@ -134,7 +134,7 @@ case class SelectDialog(mainContent: MainContent, listener: SelectDialogListener
     ): Future[Unit] = {
       pdfItem.setEnabled(true)
       graphItem.setEnabled(true)
-      val maybeTargetSv = targetSubsystem.getSubsystemWithVersion
+      val maybeTargetSv = targetSubsystem.getSubsystemWithVersion()
       targetSubsystem.setEnabled(maybeSv.isDefined)
       applyButton.disabled = maybeSv.isEmpty
       clientApiCheckbox.disabled = maybeTargetSv.isDefined || maybeSv.isEmpty
@@ -160,7 +160,7 @@ case class SelectDialog(mainContent: MainContent, listener: SelectDialogListener
         maybeTargetSv: Option[SubsystemWithVersion],
         findMatchingIcd: Boolean
     ): Future[Unit] = {
-      val maybeSv = subsystem.getSubsystemWithVersion
+      val maybeSv = subsystem.getSubsystemWithVersion()
       clientApiCheckbox.disabled = maybeTargetSv.isDefined || maybeSv.isEmpty
       searchAllCheckbox.disabled = maybeTargetSv.isDefined || maybeSv.isEmpty || !clientApi()
       maybeSv
@@ -181,8 +181,8 @@ case class SelectDialog(mainContent: MainContent, listener: SelectDialogListener
   // Swap source and target subsystems
   private def swapSubsystems(): Unit = {
     for {
-      sv2 <- targetSubsystem.getSubsystemWithVersion
-      sv1 <- subsystem.getSubsystemWithVersion
+      sv2 <- targetSubsystem.getSubsystemWithVersion()
+      sv1 <- subsystem.getSubsystemWithVersion()
     } {
       // XXX TODO FIXME: Use of futures...
       icdChooser.selectMatchingIcd(sv2, Some(sv1))
@@ -218,8 +218,8 @@ case class SelectDialog(mainContent: MainContent, listener: SelectDialogListener
 
   // Display the selected subsystems and components
   def applySettings(): Future[Unit] = {
-    val maybeSv       = subsystem.getSubsystemWithVersion
-    val maybeTargetSv = targetSubsystem.getSubsystemWithVersion
+    val maybeSv       = subsystem.getSubsystemWithVersion()
+    val maybeTargetSv = targetSubsystem.getSubsystemWithVersion()
     val maybeIcd      = icdChooser.getSelectedIcdVersion
     val showClientApi = clientApi() || maybeTargetSv.isDefined
     val searchAll = searchAllSubsystems() && maybeTargetSv.isEmpty
diff --git a/icd-web-client/src/main/scala/icd/web/client/Subsystem.scala b/icd-web-client/src/main/scala/icd/web/client/Subsystem.scala
index e2366f2d..81777f4c 100644
--- a/icd-web-client/src/main/scala/icd/web/client/Subsystem.scala
+++ b/icd-web-client/src/main/scala/icd/web/client/Subsystem.scala
@@ -95,12 +95,12 @@ case class Subsystem(
   // called when a subsystem is selected
   private def subsystemSelected(e: dom.Event): Unit = {
     for (_ <- updateSubsystemVersionOptions())
-      listener.subsystemSelected(getSubsystemWithVersion)
+      listener.subsystemSelected(getSubsystemWithVersion(subsystemOnly = true))
   }
 
   // called when a subsystem version is selected
   private def subsystemVersionSelected(e: dom.Event): Unit = {
-    listener.subsystemSelected(getSubsystemWithVersion)
+    listener.subsystemSelected(getSubsystemWithVersion())
   }
 
   // HTML markup displaying the subsystem and version comboboxes
@@ -159,10 +159,14 @@ case class Subsystem(
     }
 
   /**
-   * Gets the selected subsystem with the selected version
+   * Gets the selected subsystem with the selected version and component.
+   * If subsystemOnly is true, gets only the subsystem with no version or component selected.
    */
-  def getSubsystemWithVersion: Option[SubsystemWithVersion] = {
-    getSelectedSubsystem.map(subsystem => SubsystemWithVersion(subsystem, getSelectedSubsystemVersion, getSelectedComponent))
+  def getSubsystemWithVersion(subsystemOnly: Boolean = false): Option[SubsystemWithVersion] = {
+    getSelectedSubsystem.map(subsystem =>
+      SubsystemWithVersion(subsystem,
+        if (subsystemOnly) None else getSelectedSubsystemVersion,
+        if (subsystemOnly) None else getSelectedComponent))
   }
 
   /**
@@ -176,7 +180,7 @@ case class Subsystem(
       maybeSv: Option[SubsystemWithVersion],
       findMatchingIcd: Boolean = true
   ): Future[Unit] = {
-    if (maybeSv == getSubsystemWithVersion)
+    if (maybeSv == getSubsystemWithVersion())
       Future.successful()
     else {
       maybeSv match {
@@ -249,7 +253,7 @@ case class Subsystem(
         case None    =>
           versionItem.value = unpublishedVersion
       }
-      listener.subsystemSelected(getSubsystemWithVersion, findMatchingIcd = false)
+      listener.subsystemSelected(getSubsystemWithVersion(), findMatchingIcd = false)
     }
   }