[LyX/master] "System Default" viewer/editor option

[Juergen Spitzmueller]

commit 9e645a5cfc9d6c3e66d627002e68384c92c4d0b8
Author: Daniel Ramoeller <d.lyx at web.de>
Date:   Sun Aug 7 17:57:39 2022 +0200

    "System Default" viewer/editor option
    
    Fix for bug #12571. More user friendly way to set the system default application aka "auto" option.
---
 src/frontends/qt/GuiPrefs.cpp |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/src/frontends/qt/GuiPrefs.cpp b/src/frontends/qt/GuiPrefs.cpp
index 31da129..e607471 100644
--- a/src/frontends/qt/GuiPrefs.cpp
+++ b/src/frontends/qt/GuiPrefs.cpp
@@ -2325,6 +2325,7 @@ void PrefFileformats::updateViewers()
 	viewerCO->blockSignals(true);
 	viewerCO->clear();
 	viewerCO->addItem(qt_("None"), QString());
+	viewerCO->addItem(qt_("System Default"), QString("auto"));
 	updateComboBox(viewer_alternatives, f.name(), viewerCO);
 	viewerCO->addItem(qt_("Custom"), QString("custom viewer"));
 	viewerCO->blockSignals(false);
@@ -2348,6 +2349,7 @@ void PrefFileformats::updateEditors()
 	editorCO->blockSignals(true);
 	editorCO->clear();
 	editorCO->addItem(qt_("None"), QString());
+	editorCO->addItem(qt_("System Default"), QString("auto"));
 	updateComboBox(editor_alternatives, f.name(), editorCO);
 	editorCO->addItem(qt_("Custom"), QString("custom editor"));
 	editorCO->blockSignals(false);