Fix subject column after re-arranging cols

program/js/app.js

@@ -1501,6 +1501,9 @@ function rcube_webmail()
     if ((found = $.inArray('flag', this.env.coltypes)) >= 0)
       this.set_env('flagged_col', found);
 
+    if ((found = $.inArray('subject', this.env.coltypes)) >= 0)
+      this.set_env('subject_col', found);
+
     this.http_post('save-pref', { '_name':'list_cols', '_value':this.env.coltypes });
   };
 

program/js/list.js

@@ -1393,6 +1393,10 @@ column_replace: function(from, to)
   // update subject column position
   if (this.subject_col == from)
     this.subject_col = to > from ? to - 1 : to;
+  else if (this.subject_col < from && to <= this.subject_col)
+    this.subject_col++;
+  else if (this.subject_col > from && to >= this.subject_col)
+    this.subject_col--;
 
   this.triggerEvent('column_replace');
 }