From a8947aaad876bfdf8c5b2234ef300ef790112b61 Mon Sep 17 00:00:00 2001
From: Juergen Spitzmueller <spitz@lyx.org>
Date: Mon, 8 Aug 2022 09:49:51 +0200
Subject: [PATCH] Amend 9e645a5cfc9d6c3e66d

Only show "System Default" if auto-open is available for the current
format.
---
 src/frontends/qt/GuiPrefs.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/frontends/qt/GuiPrefs.cpp b/src/frontends/qt/GuiPrefs.cpp
index e607471299..5fa3b940d4 100644
--- a/src/frontends/qt/GuiPrefs.cpp
+++ b/src/frontends/qt/GuiPrefs.cpp
@@ -2325,7 +2325,8 @@ void PrefFileformats::updateViewers()
 	viewerCO->blockSignals(true);
 	viewerCO->clear();
 	viewerCO->addItem(qt_("None"), QString());
-	viewerCO->addItem(qt_("System Default"), QString("auto"));
+	if (os::canAutoOpenFile(f.extension(), os::VIEW))
+		viewerCO->addItem(qt_("System Default"), QString("auto"));
 	updateComboBox(viewer_alternatives, f.name(), viewerCO);
 	viewerCO->addItem(qt_("Custom"), QString("custom viewer"));
 	viewerCO->blockSignals(false);
@@ -2349,7 +2350,8 @@ void PrefFileformats::updateEditors()
 	editorCO->blockSignals(true);
 	editorCO->clear();
 	editorCO->addItem(qt_("None"), QString());
-	editorCO->addItem(qt_("System Default"), QString("auto"));
+	if (os::canAutoOpenFile(f.extension(), os::EDIT))
+		editorCO->addItem(qt_("System Default"), QString("auto"));
 	updateComboBox(editor_alternatives, f.name(), editorCO);
 	editorCO->addItem(qt_("Custom"), QString("custom editor"));
 	editorCO->blockSignals(false);