Use aria-describedby to link notice and input again

https://www.w3.org/WAI/tutorials/forms/instructions/#using-aria-describedby

app/helpers/champ_helper.rb

@@ -25,4 +25,10 @@ module ChampHelper
     end
     simple_format(auto_linked_text, {}, sanitize: false)
   end
+
+  def describedby_id(champ)
+    if champ.description.present?
+      "desc-#{champ.type_de_champ.id}-#{champ.row}"
+    end
+  end
 end

app/views/shared/dossiers/editable_champs/_champ_label.html.haml

@@ -8,4 +8,4 @@
       = "modifié le #{try_format_datetime(champ.updated_at)}"
 
 - if champ.description.present?
-  .notice= string_to_html(champ.description)
+  .notice{ id: describedby_id(champ) }= string_to_html(champ.description)

app/views/shared/dossiers/editable_champs/_text.html.haml

@@ -1,3 +1,4 @@
 = form.text_field :value,
   placeholder: champ.libelle,
-  required: champ.mandatory?
+  required: champ.mandatory?,
+  aria: { describedby: describedby_id(champ) }