CSS cleanups and preparations

template/_tree.hbs

@@ -11,7 +11,18 @@
     <link rel="stylesheet" href="{{ asset (cat 'css/' this) }}">
     {{/each}}
 
-    <script type="module">
+    <script type="module" async>
+        import "treehouse/spells.js";
+        import "treehouse/tree.js";
+        import "treehouse/ulid.js";
+
+        // We want to let the user have a selection on collapsible blocks without collapsing them when
+        // the user finishes marking their selection.
+        document.addEventListener("click", event => {
+        if (getSelection().type == "Range") {
+            event.preventDefault();
+        }
+
         {{!-- Go through the import map for each script. --}}
         {{#each page.scripts}}
         import "{{ this }}";