Index: gc_lang/fr/webext/content_scripts/api.js
==================================================================
--- gc_lang/fr/webext/content_scripts/api.js
+++ gc_lang/fr/webext/content_scripts/api.js
@@ -85,5 +85,11 @@
         } else {
             console.log("[Grammalecte API] Error: one or several parameters aren’t string.");
         }
     }
 }
+
+/*
+    Tell to the webpage that the Grammalecte API is ready.
+*/
+document.dispatchEvent(new Event('GrammalecteLoaded'));
+

Index: gc_lang/fr/webext/content_scripts/init.js
==================================================================
--- gc_lang/fr/webext/content_scripts/init.js
+++ gc_lang/fr/webext/content_scripts/init.js
@@ -518,18 +518,15 @@
 
 
 
 /*
     Callable API for the webpage.
-    The API script must be injected this way to be callable by the page
-*/
-let xScriptGrammalecteAPI = document.createElement("script");
-xScriptGrammalecteAPI.src = browser.extension.getURL("content_scripts/api.js");
-document.documentElement.appendChild(xScriptGrammalecteAPI);
 
+*/
 document.addEventListener("GrammalecteCall", function (xEvent) {
     // GrammalecteCall events are dispatched by functions in the API script
+    // The script is loaded below.
     try {
         let oCommand = xEvent.detail;
         switch (oCommand.sCommand) {
             case "openPanelForNode":
                 if (oCommand.xNode) {
@@ -565,12 +562,17 @@
     }
     catch (e) {
         showError(e);
     }
 });
+
+// The API script must be injected this way to be callable by the page
+let xScriptGrammalecteAPI = document.createElement("script");
+xScriptGrammalecteAPI.src = browser.extension.getURL("content_scripts/api.js");
+document.documentElement.appendChild(xScriptGrammalecteAPI);
 
 
 /*
     Note:
     Initialization starts when the background is connected.
     See: oGrammalecteBackgroundPort.listen() -> case "init"
 */