Fix 1698

src/Dialogs/PreferencesDialog.vala

@@ -22,7 +22,11 @@ public class Scratch.Dialogs.Preferences : Granite.Dialog {
         var general_box = new Gtk.Box (VERTICAL, 12);
         general_box.add (new Granite.HeaderLabel (_("General")));
         general_box.add (new SettingSwitch (_("Save files when changed"), "autosave"));
-        general_box.add (new SettingSwitch (_("Strip trailing whitespace on save"), "strip-trailing-on-save"));
+        general_box.add (new SettingSwitch (
+            _("Strip trailing whitespace on save"),
+            "strip-trailing-on-save",
+            _("For syntax highlighted files, except Markdown and YAML")
+        ));
         general_box.add (new SettingSwitch (
             _("Smart cut/copy lines"),
             "smart-cut-copy",

src/Services/Document.vala

@@ -1319,6 +1319,11 @@ namespace Scratch.Services {
                 return;
             }
 
+            var lang_id = source_view.language.id;
+            if (lang_id == "markdown" || lang_id == "yaml") {
+                return;
+            }
+
             var source_buffer = (Gtk.SourceBuffer)source_view.buffer;
             Gtk.TextIter iter;