diff --git a/app/controllers/instructeurs/dossiers_controller.rb b/app/controllers/instructeurs/dossiers_controller.rb
index ae148d258..c95fb1ee5 100644
--- a/app/controllers/instructeurs/dossiers_controller.rb
+++ b/app/controllers/instructeurs/dossiers_controller.rb
@@ -370,9 +370,24 @@ module Instructeurs
 
     def pieces_jointes
       @dossier = current_instructeur.dossiers.find(params[:dossier_id])
-      @champs_with_pieces_jointes = @dossier
+
+      champs_attachments_and_libelles = @dossier
         .champs
         .filter { _1.class.in?([Champs::PieceJustificativeChamp, Champs::TitreIdentiteChamp]) }
+        .flat_map do |c|
+          c.piece_justificative_file.map do |attachment|
+            [attachment, c.libelle]
+          end
+        end
+
+      commentaires_attachments_and_libelles = @dossier
+        .commentaires
+        .map(&:piece_jointe)
+        .map(&:attachments)
+        .flatten
+        .map { [_1, 'Messagerie'] }
+
+      @attachments_and_libelles = champs_attachments_and_libelles + commentaires_attachments_and_libelles
     end
 
     private
diff --git a/app/models/concerns/blob_image_processor_concern.rb b/app/models/concerns/blob_image_processor_concern.rb
index 3b92ad4e4..d69e380f5 100644
--- a/app/models/concerns/blob_image_processor_concern.rb
+++ b/app/models/concerns/blob_image_processor_concern.rb
@@ -8,11 +8,19 @@ module BlobImageProcessorConcern
   end
 
   def representation_required?
-    attachments.any? { _1.record.class == Champs::TitreIdentiteChamp || _1.record.class == Champs::PieceJustificativeChamp }
+    from_champ? || from_messagerie?
   end
 
   private
 
+  def from_champ?
+    attachments.any? { _1.record.class == Champs::TitreIdentiteChamp || _1.record.class == Champs::PieceJustificativeChamp }
+  end
+
+  def from_messagerie?
+    attachments.any? { _1.record.class == Commentaire }
+  end
+
   def watermark_required?
     attachments.any? { _1.record.class == Champs::TitreIdentiteChamp }
   end
diff --git a/app/tasks/maintenance/create_previews_for_pjs_from_messagerie_task.rb b/app/tasks/maintenance/create_previews_for_pjs_from_messagerie_task.rb
new file mode 100644
index 000000000..b75c530b9
--- /dev/null
+++ b/app/tasks/maintenance/create_previews_for_pjs_from_messagerie_task.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+module Maintenance
+  class CreatePreviewsForPjsFromMessagerieTask < MaintenanceTasks::Task
+    attribute :start_text, :string
+    validates :start_text, presence: true
+
+    attribute :end_text, :string
+    validates :end_text, presence: true
+
+    def collection
+      start_date = DateTime.parse(start_text)
+      end_date = DateTime.parse(end_text)
+
+      Dossier
+        .state_en_construction_ou_instruction
+        .where(depose_at: start_date..end_date)
+    end
+
+    def process(dossier)
+      commentaire_ids = Commentaire
+        .where(dossier_id: dossier)
+        .pluck(:id)
+
+      attachments = ActiveStorage::Attachment
+        .where(record_id: commentaire_ids)
+
+      attachments.each do |attachment|
+        next if !(attachment.previewable? && attachment.representation_required?)
+        attachment.preview(resize_to_limit: [400, 400]).processed unless attachment.preview(resize_to_limit: [400, 400]).image.attached?
+      rescue MiniMagick::Error, ActiveStorage::Error
+      end
+    end
+  end
+end
diff --git a/app/tasks/maintenance/create_variants_for_pjs_from_messagerie__task.rb b/app/tasks/maintenance/create_variants_for_pjs_from_messagerie__task.rb
new file mode 100644
index 000000000..fa1eb30d2
--- /dev/null
+++ b/app/tasks/maintenance/create_variants_for_pjs_from_messagerie__task.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+module Maintenance
+  class CreateVariantsForPjsFromMessagerieTask < MaintenanceTasks::Task
+    attribute :start_text, :string
+    validates :start_text, presence: true
+
+    attribute :end_text, :string
+    validates :end_text, presence: true
+
+    def collection
+      start_date = DateTime.parse(start_text)
+      end_date = DateTime.parse(end_text)
+
+      Dossier
+        .state_en_construction_ou_instruction
+        .where(depose_at: start_date..end_date)
+    end
+
+    def process(dossier)
+      commentaire_ids = Commentaire
+        .where(dossier_id: dossier)
+        .pluck(:id)
+
+      attachments = ActiveStorage::Attachment
+        .where(record_id: commentaire_ids)
+
+      attachments.each do |attachment|
+        next if !(attachment.variable? && attachment.representation_required?)
+        attachment.variant(resize_to_limit: [400, 400]).processed if attachment.variant(resize_to_limit: [400, 400]).key.nil?
+        if attachment.blob.content_type.in?(RARE_IMAGE_TYPES) && attachment.variant(resize_to_limit: [2000, 2000]).key.nil?
+          attachment.variant(resize_to_limit: [2000, 2000]).processed
+        end
+      rescue MiniMagick::Error, ActiveStorage::Error
+      end
+    end
+  end
+end
diff --git a/app/views/instructeurs/dossiers/pieces_jointes.html.haml b/app/views/instructeurs/dossiers/pieces_jointes.html.haml
index d770433d4..97ab75c55 100644
--- a/app/views/instructeurs/dossiers/pieces_jointes.html.haml
+++ b/app/views/instructeurs/dossiers/pieces_jointes.html.haml
@@ -4,33 +4,32 @@
 
 .fr-container
   .gallery.gallery-pieces-jointes{ "data-controller": "lightbox" }
-    - @champs_with_pieces_jointes.each do |champ|
-      - champ.piece_justificative_file.with_all_variant_records.each do |attachment|
-        .gallery-item
-          - blob = attachment.blob
-          - if displayable_pdf?(blob)
-            = link_to blob.url, id: blob.id, data: { iframe: true, src: blob.url }, class: 'gallery-link', type: blob.content_type, title: "#{champ.libelle} -- #{blob.filename}" do
-              .thumbnail
-                = image_tag(preview_url_for(attachment), loading: :lazy)
-                .fr-btn.fr-btn--tertiary.fr-btn--icon-left.fr-icon-eye{ role: :button }
-                  Visualiser
-            .champ-libelle
-              = champ.libelle.truncate(25)
-            = render Attachment::ShowComponent.new(attachment: attachment, truncate: true)
-
-          - elsif displayable_image?(blob)
-            = link_to image_url(blob_url(attachment)), title: "#{champ.libelle} -- #{blob.filename}", data: { src: blob.url }, class: 'gallery-link' do
-              .thumbnail
-                = image_tag(variant_url_for(attachment), loading: :lazy)
-                .fr-btn.fr-btn--tertiary.fr-btn--icon-left.fr-icon-eye{ role: :button }
-                  Visualiser
-            .champ-libelle
-              = champ.libelle.truncate(25)
-            = render Attachment::ShowComponent.new(attachment: attachment, truncate: true)
-
-          - else
+    - @attachments_and_libelles.each do |attachment, libelle|
+      .gallery-item
+        - blob = attachment.blob
+        - if displayable_pdf?(blob)
+          = link_to blob.url, id: blob.id, data: { iframe: true, src: blob.url }, class: 'gallery-link', type: blob.content_type, title: "#{libelle} -- #{blob.filename}" do
             .thumbnail
-              = image_tag('apercu-indisponible.png')
-            .champ-libelle
-              = champ.libelle.truncate(25)
-            = render Attachment::ShowComponent.new(attachment: attachment, truncate: true)
+              = image_tag(preview_url_for(attachment), loading: :lazy)
+              .fr-btn.fr-btn--tertiary.fr-btn--icon-left.fr-icon-eye{ role: :button }
+                Visualiser
+          .champ-libelle
+            = libelle.truncate(25)
+          = render Attachment::ShowComponent.new(attachment: attachment, truncate: true)
+
+        - elsif displayable_image?(blob)
+          = link_to image_url(blob_url(attachment)), title: "#{libelle} -- #{blob.filename}", data: { src: blob.url }, class: 'gallery-link' do
+            .thumbnail
+              = image_tag(variant_url_for(attachment), loading: :lazy)
+              .fr-btn.fr-btn--tertiary.fr-btn--icon-left.fr-icon-eye{ role: :button }
+                Visualiser
+          .champ-libelle
+            = libelle.truncate(25)
+          = render Attachment::ShowComponent.new(attachment: attachment, truncate: true)
+
+        - else
+          .thumbnail
+            = image_tag('apercu-indisponible.png')
+          .champ-libelle
+            = libelle.truncate(25)
+          = render Attachment::ShowComponent.new(attachment: attachment, truncate: true)
diff --git a/spec/controllers/instructeurs/dossiers_controller_spec.rb b/spec/controllers/instructeurs/dossiers_controller_spec.rb
index 2ad0cb84d..a8ae359ab 100644
--- a/spec/controllers/instructeurs/dossiers_controller_spec.rb
+++ b/spec/controllers/instructeurs/dossiers_controller_spec.rb
@@ -1466,25 +1466,37 @@ describe Instructeurs::DossiersController, type: :controller do
   describe '#pieces_jointes' do
     let(:procedure) { create(:procedure, :published, types_de_champ_public: [{ type: :piece_justificative }], instructeurs:) }
     let(:dossier) { create(:dossier, :en_construction, :with_populated_champs, procedure: procedure) }
-    let(:path) { 'spec/fixtures/files/logo_test_procedure.png' }
+    let(:logo_path) { 'spec/fixtures/files/logo_test_procedure.png' }
+    let(:rib_path) { 'spec/fixtures/files/RIB.pdf' }
+    let(:commentaire) { create(:commentaire, dossier: dossier) }
 
     before do
       dossier.champs.first.piece_justificative_file.attach(
-        io: File.open(path),
+        io: File.open(logo_path),
         filename: "logo_test_procedure.png",
         content_type: "image/png",
         metadata: { virus_scan_result: ActiveStorage::VirusScanner::SAFE }
       )
+
+      commentaire.piece_jointe.attach(
+        io: File.open(rib_path),
+        filename: "RIB.pdf",
+        content_type: "application/pdf",
+        metadata: { virus_scan_result: ActiveStorage::VirusScanner::SAFE }
+      )
+
       get :pieces_jointes, params: {
         procedure_id: procedure.id,
         dossier_id: dossier.id
       }
     end
 
-    it do
+    it 'returns pieces jointes from champs and from messagerie' do
       expect(response.body).to include('Télécharger le fichier toto.txt')
       expect(response.body).to include('Télécharger le fichier logo_test_procedure.png')
+      expect(response.body).to include('Télécharger le fichier RIB.pdf')
       expect(response.body).to include('Visualiser')
+      expect(assigns(:attachments_and_libelles).count).to eq 3
     end
   end
 end
diff --git a/spec/tasks/maintenance/create_previews_for_pjs_from_messagerie_task_spec.rb b/spec/tasks/maintenance/create_previews_for_pjs_from_messagerie_task_spec.rb
new file mode 100644
index 000000000..245c1971c
--- /dev/null
+++ b/spec/tasks/maintenance/create_previews_for_pjs_from_messagerie_task_spec.rb
@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+module Maintenance
+  RSpec.describe CreatePreviewsForPjsFromMessagerieTask do
+    describe "#process" do
+      let(:procedure) { create(:procedure_with_dossiers) }
+      let(:dossier) { procedure.dossiers.first }
+      let(:commentaire) { create(:commentaire, dossier: dossier) }
+
+      before do
+        commentaire.piece_jointe.attach(
+          io: File.open(file_path),
+          filename: file_name,
+          content_type: content_type,
+          metadata: { virus_scan_result: ActiveStorage::VirusScanner::SAFE }
+        )
+        dossier.update(
+          depose_at: Date.new(2024, 05, 23),
+          state: "en_construction"
+        )
+      end
+
+      subject(:process) { described_class.process(dossier) }
+
+      context "when pj is a pdf" do
+        let(:file_path) { 'spec/fixtures/files/RIB.pdf' }
+        let(:file_name) { 'RIB.pdf' }
+        let(:content_type) { 'application/pdf' }
+
+        it "creates a preview" do
+          expect(commentaire.piece_jointe.first.preview(resize_to_limit: [400, 400]).image.attached?).to be false
+          expect { subject }.to change { commentaire.piece_jointe.first.reload.preview(resize_to_limit: [400, 400]).image.attached? }
+        end
+      end
+    end
+  end
+end
diff --git a/spec/tasks/maintenance/create_variants_for_pjs_from_messagerie__task_spec.rb b/spec/tasks/maintenance/create_variants_for_pjs_from_messagerie__task_spec.rb
new file mode 100644
index 000000000..0428e6d0b
--- /dev/null
+++ b/spec/tasks/maintenance/create_variants_for_pjs_from_messagerie__task_spec.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+module Maintenance
+  RSpec.describe CreateVariantsForPjsFromMessagerieTask do
+    describe "#process" do
+      let(:procedure) { create(:procedure_with_dossiers) }
+      let(:dossier) { procedure.dossiers.first }
+      let(:commentaire) { create(:commentaire, dossier: dossier) }
+
+      before do
+        commentaire.piece_jointe.attach(
+          io: File.open(file_path),
+          filename: file_name,
+          content_type: content_type,
+          metadata: { virus_scan_result: ActiveStorage::VirusScanner::SAFE }
+        )
+        dossier.update(
+          depose_at: Date.new(2024, 05, 23),
+          state: "en_construction"
+        )
+      end
+
+      subject(:process) { described_class.process(dossier) }
+
+      context "when pj is a classical format image" do
+        let(:file_path) { 'spec/fixtures/files/logo_test_procedure.png' }
+        let(:file_name) { 'logo_test_procedure.png' }
+        let(:content_type) { 'image/png' }
+
+        it "creates a variant" do
+          expect(commentaire.piece_jointe.first.variant(resize_to_limit: [400, 400]).key).to be_nil
+          expect { subject }.to change { ActiveStorage::VariantRecord.count }.by(1)
+          expect(commentaire.piece_jointe.first.variant(resize_to_limit: [400, 400]).key).not_to be_nil
+          expect(commentaire.piece_jointe.first.variant(resize_to_limit: [2000, 2000]).key).to be_nil
+        end
+      end
+
+      context "when pj is a rare format image" do
+        let(:file_path) { 'spec/fixtures/files/pencil.tiff' }
+        let(:file_name) { 'pencil.tiff' }
+        let(:content_type) { 'image/tiff' }
+
+        it "creates a variant" do
+          expect(commentaire.piece_jointe.first.variant(resize_to_limit: [400, 400]).key).to be_nil
+          expect { subject }.to change { ActiveStorage::VariantRecord.count }.by(2)
+          expect(commentaire.piece_jointe.first.variant(resize_to_limit: [400, 400]).key).not_to be_nil
+          expect(commentaire.piece_jointe.first.variant(resize_to_limit: [2000, 2000]).key).not_to be_nil
+        end
+      end
+    end
+  end
+end