fix dashboard page jump around at refresh, save instance button

tabler/index.html

@@ -112,7 +112,7 @@
               <div class="card-header">
                 <h4 class="card-title">Most Visited Pages</h4>
               </div>
-              <div class="table-responsive">
+              <div id="ovpn_table_container" class="table-responsive">
                 <table id="ovpn_table" class="table card-table table-vcenter">
                   <!-- <thead>
                     <tr>
@@ -353,11 +353,20 @@
           });
         });
 
-
+        $("#ovpn_table_container").height($("#ovpn_table").height()); // set fixed height for table container to prevent page from scrolling to top
       });
     }
     update_stat();
     setInterval(update_stat, 1000);
+
+    function save_current_config(){
+      $.get("/save_instance", (data, textStatus)=>{
+        if(textStatus=="success"){
+          alert("saved")
+        }
+      });
+    }
+
   </script>