diff --git a/Gemfile.lock b/Gemfile.lock
index 3c58933a0..52442360c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -423,7 +423,7 @@ GEM
       ruby2_keywords (~> 0.0.1)
     netrc (0.11.0)
     nio4r (2.5.7)
-    nokogiri (1.11.3)
+    nokogiri (1.11.4)
       mini_portile2 (~> 2.5.0)
       racc (~> 1.4)
     open4 (1.3.4)
@@ -471,7 +471,7 @@ GEM
       byebug (~> 11.0)
       pry (~> 0.13.0)
     public_suffix (4.0.6)
-    puma (5.2.1)
+    puma (5.3.1)
       nio4r (~> 2.0)
     pundit (2.1.0)
       activesupport (>= 3.0.0)
diff --git a/app/controllers/recherche_controller.rb b/app/controllers/recherche_controller.rb
index 6d02bcbea..f2d96ffb6 100644
--- a/app/controllers/recherche_controller.rb
+++ b/app/controllers/recherche_controller.rb
@@ -10,25 +10,24 @@ class RechercheController < ApplicationController
   def index
     @search_terms = search_terms
 
-    @instructeur_dossiers_ids = current_instructeur&.dossiers&.ids || []
-    matching_dossiers_ids = DossierSearchService
-      .matching_dossiers(@instructeur_dossiers_ids, @search_terms, with_annotation: true)
-      .to_set
+    @instructeur_dossiers_ids = DossierSearchService
+      .matching_dossiers(current_instructeur&.dossiers, @search_terms, with_annotation: true)
 
-    @dossier_avis_ids_h = current_expert&.avis&.pluck(:dossier_id, :id).to_h || {}
-    expert_dossiers_ids = @dossier_avis_ids_h.keys
-    matching_dossiers_ids.merge(DossierSearchService.matching_dossiers(expert_dossiers_ids, @search_terms))
+    expert_dossier_ids = DossierSearchService
+      .matching_dossiers(current_expert&.dossiers, @search_terms)
 
-    @dossiers_count = matching_dossiers_ids.count
+    matching_dossiers_ids = (@instructeur_dossiers_ids + expert_dossier_ids).uniq
 
     @paginated_ids = Kaminari
-      .paginate_array(matching_dossiers_ids.to_a)
+      .paginate_array(matching_dossiers_ids)
       .page(page)
       .per(ITEMS_PER_PAGE)
 
     @projected_dossiers = DossierProjectionService.project(@paginated_ids, PROJECTIONS)
 
+    @dossiers_count = matching_dossiers_ids.count
     @followed_dossiers_id = current_instructeur&.followed_dossiers&.where(id: @paginated_ids)&.ids || []
+    @dossier_avis_ids_h = current_expert&.avis&.where(dossier_id: @paginated_ids)&.pluck(:dossier_id, :id).to_h || {}
   end
 
   private
diff --git a/app/javascript/packs/application.js b/app/javascript/packs/application.js
index 940713e7b..d191c84c9 100644
--- a/app/javascript/packs/application.js
+++ b/app/javascript/packs/application.js
@@ -19,6 +19,7 @@ import '../new_design/procedure-context';
 import '../new_design/procedure-form';
 import '../new_design/spinner';
 import '../new_design/support';
+import '../new_design/messagerie';
 import '../new_design/dossiers/auto-save';
 import '../new_design/dossiers/auto-upload';
 
diff --git a/app/models/dossier.rb b/app/models/dossier.rb
index cd288cae0..0ed94a2bc 100644
--- a/app/models/dossier.rb
+++ b/app/models/dossier.rb
@@ -535,14 +535,10 @@ class Dossier < ApplicationRecord
   end
 
   def avis_for_expert(expert)
-    if expert.dossiers.include?(self)
-      avis.order(created_at: :asc)
-    else
-      avis
-        .where(confidentiel: false)
-        .or(avis.where(claimant: expert))
-        .order(created_at: :asc)
-    end
+    Avis
+      .where(dossier_id: id, confidentiel: false)
+      .or(Avis.where(id: expert.avis))
+      .order(created_at: :asc)
   end
 
   def owner_name
diff --git a/app/services/dossier_search_service.rb b/app/services/dossier_search_service.rb
index dc5eab1a1..a3f95a3f5 100644
--- a/app/services/dossier_search_service.rb
+++ b/app/services/dossier_search_service.rb
@@ -1,7 +1,11 @@
 class DossierSearchService
-  def self.matching_dossiers(ids, search_terms, with_annotations = false)
-    dossier_by_exact_id(ids, search_terms)
-      .presence || dossier_by_full_text(ids, search_terms, with_annotations)
+  def self.matching_dossiers(dossiers, search_terms, with_annotations = false)
+    if dossiers.nil?
+      []
+    else
+      dossier_by_exact_id(dossiers, search_terms)
+        .presence || dossier_by_full_text(dossiers, search_terms, with_annotations)
+    end
   end
 
   def self.matching_dossiers_for_user(search_terms, user)
@@ -11,20 +15,20 @@ class DossierSearchService
 
   private
 
-  def self.dossier_by_exact_id(ids, search_terms)
+  def self.dossier_by_exact_id(dossiers, search_terms)
     id = search_terms.to_i
     if id != 0 && id_compatible?(id) # Sometimes instructeur is searching dossiers with a big number (ex: SIRET), ActiveRecord can't deal with them and throws ActiveModel::RangeError. id_compatible? prevents this.
-      ids.filter { |dossier_id| dossier_id == id }.uniq
+      dossiers.where(id: id).ids
     else
-      Dossier.none
+      []
     end
   end
 
-  def self.dossier_by_full_text(ids, search_terms, with_annotations)
+  def self.dossier_by_full_text(dossiers, search_terms, with_annotations)
     ts_vector = "to_tsvector('french', #{with_annotations ? 'dossiers.search_terms || dossiers.private_search_terms' : 'dossiers.search_terms'})"
     ts_query = "to_tsquery('french', #{Dossier.connection.quote(to_tsquery(search_terms))})"
 
-    Dossier.where(id: ids)
+    dossiers
       .where("#{ts_vector} @@ #{ts_query}")
       .order(Arel.sql("COALESCE(ts_rank(#{ts_vector}, #{ts_query}), 0) DESC"))
       .pluck('id')
diff --git a/spec/models/dossier_spec.rb b/spec/models/dossier_spec.rb
index 7d87596c1..8ae36a3d7 100644
--- a/spec/models/dossier_spec.rb
+++ b/spec/models/dossier_spec.rb
@@ -337,20 +337,22 @@ describe Dossier do
       it { expect(dossier.avis_for_expert(expert_2)).not_to match([avis]) }
     end
 
-    context 'when there is a public advice asked from one expert to another' do
-      let!(:avis) { create(:avis, dossier: dossier, claimant: instructeur, experts_procedure: experts_procedure_2, confidentiel: false) }
+    context 'when there is a public advice asked from one instructeur to an expert' do
+      let!(:avis_1) { create(:avis, dossier: dossier, claimant: instructeur, experts_procedure: experts_procedure, confidentiel: false) }
+      let!(:avis_2) { create(:avis, dossier: dossier, claimant: instructeur, experts_procedure: experts_procedure_2, confidentiel: false) }
 
-      it { expect(dossier.avis_for_instructeur(instructeur)).to match([avis]) }
-      it { expect(dossier.avis_for_expert(expert_1)).to match([avis]) }
-      it { expect(dossier.avis_for_expert(expert_2)).to match([avis]) }
+      it { expect(dossier.avis_for_instructeur(instructeur)).to match([avis_1, avis_2]) }
+      it { expect(dossier.avis_for_expert(expert_1)).to match([avis_1, avis_2]) }
+      it { expect(dossier.avis_for_expert(expert_2)).to match([avis_1, avis_2]) }
     end
 
-    context 'when there is a private advice asked from one expert to another' do
-      let!(:avis) { create(:avis, dossier: dossier, claimant: instructeur, experts_procedure: experts_procedure_2, confidentiel: true) }
+    context 'when there is a private advice asked from one instructeur to an expert' do
+      let!(:avis_1) { create(:avis, dossier: dossier, claimant: instructeur, experts_procedure: experts_procedure, confidentiel: true) }
+      let!(:avis_2) { create(:avis, dossier: dossier, claimant: instructeur, experts_procedure: experts_procedure_2, confidentiel: true) }
 
-      it { expect(dossier.avis_for_instructeur(instructeur)).to match([avis]) }
-      it { expect(dossier.avis_for_expert(expert_1)).not_to match([avis]) }
-      it { expect(dossier.avis_for_expert(expert_2)).to match([avis]) }
+      it { expect(dossier.avis_for_instructeur(instructeur)).to match([avis_1, avis_2]) }
+      it { expect(dossier.avis_for_expert(expert_1)).to match([avis_1]) }
+      it { expect(dossier.avis_for_expert(expert_2)).to match([avis_2]) }
     end
 
     context 'when they are a lot of advice' do