Index: gc_lang/fr/webext/content_scripts/panel.css
==================================================================
--- gc_lang/fr/webext/content_scripts/panel.css
+++ gc_lang/fr/webext/content_scripts/panel.css
@@ -40,13 +40,14 @@
 .grammalecte_panel_label {
     display: inline-block;
     padding: 0 10px;
 }
 .grammalecte_panel_invisible_marker {
-    font-size: 1px;
     position: absolute;
-    visibility: hidden;
+    /*visibility: hidden;*/
+    font-size: 6px;
+    color: hsl(210, 0%, 90%); /* same color than panel_bar background */
 }
 
 .grammalecte_panel_commands {
     float: right;
 }