Index: gc_lang/fr/webext/content_scripts/panel_gc.js
==================================================================
--- gc_lang/fr/webext/content_scripts/panel_gc.js
+++ gc_lang/fr/webext/content_scripts/panel_gc.js
@@ -359,11 +359,11 @@
             if (xNodeErr.dataset.gc_message.includes(" #")) {
                 xNodeErr.dataset.line_id = oErr['sLineId'];
                 xNodeErr.dataset.rule_id = oErr['sRuleId'];
             }
             xNodeErr.dataset.suggestions = oErr["aSuggestions"].join("|");
-            if (oErr.hasOwnProperty("aColor")) {
+            if (oErr.hasOwnProperty("aColor")  &&  Array.isArray(oErr["aColor"])  &&  oErr["aColor"].length === 3) {
                 let sHue = oErr["aColor"][0].toString();
                 let sSat = oErr["aColor"][1].toString();
                 let sLum = oErr["aColor"][2].toString();
                 xNodeErr.style.color = `hsl(${sHue}, ${sSat}%, 15%)`;
                 xNodeErr.style.backgroundColor = `hsl(${sHue}, ${sSat}%, 85%)`;