commented code for the addon reviewers

src/js/contentscript-end.js

@@ -231,6 +231,10 @@ var uBlockCollapser = (function() {
 
     var primeLocalIFrame = function(iframe) {
         // Should probably also copy injected styles.
+        // The injected scripts are those which were injected in the current
+        // document, from within the `contentscript-start.js / injectScripts`,
+        // and which scripts are selectively looked-up from:
+        // https://github.com/gorhill/uBlock/blob/master/assets/ublock/resources.txt
         if ( vAPI.injectedScripts ) {
             var scriptTag = document.createElement('script');
             scriptTag.appendChild(document.createTextNode(vAPI.injectedScripts));

src/js/contentscript-start.js

@@ -124,8 +124,10 @@ var netFilters = function(details) {
 
 // Create script tags and assign data URIs looked up from our library of
 // redirection resources: Sometimes it is useful to use these resources as
-// standalone scriptlets.
-// Library of redirection resources:
+// standalone scriptlets. These scriptlets are injected from within the
+// content scripts because what must be injected, if anything, depends on the
+// currently active filters, as selected by the user.
+// Library of redirection resources is located at:
 // https://github.com/gorhill/uBlock/blob/master/assets/ublock/resources.txt
 
 var injectScripts = function(scripts) {