Experimentally try setting Ace's auto complete exactMatch flag to true

app/renderer/acesrc/ext-language_tools.js

@@ -1293,7 +1293,7 @@ var snippetManager = require("./snippets").snippetManager;
 var Autocomplete = function() {
     this.autoInsert = false;
     this.autoSelect = true;
-    this.exactMatch = false;
+    this.exactMatch = true;
     this.gatherCompletionsId = 0;
     this.keyboardHandler = new HashHandler();
     this.keyboardHandler.bindKeys(this.commands);