diff --git a/app/controllers/new_user/dossiers_controller.rb b/app/controllers/new_user/dossiers_controller.rb
index 0cdb5a55a..7093665cf 100644
--- a/app/controllers/new_user/dossiers_controller.rb
+++ b/app/controllers/new_user/dossiers_controller.rb
@@ -28,9 +28,6 @@ module NewUser
     def show
       if dossier.brouillon?
         redirect_to brouillon_dossier_path(dossier)
-
-      elsif !Flipflop.new_dossier_details?
-        redirect_to users_dossier_recapitulatif_path(dossier)
       end
 
       @dossier = dossier
@@ -125,15 +122,7 @@ module NewUser
         flash.now.alert = errors
         render :modifier
       else
-        if Flipflop.new_dossier_details?
-          redirect_to demande_dossier_path(@dossier)
-        else
-          if current_user.owns?(dossier)
-            redirect_to users_dossier_recapitulatif_path(@dossier)
-          else
-            redirect_to users_dossiers_invite_path(@dossier.invite_for_user(current_user))
-          end
-        end
+        redirect_to demande_dossier_path(@dossier)
       end
     end
 
diff --git a/app/controllers/users/dossiers/invites_controller.rb b/app/controllers/users/dossiers/invites_controller.rb
index 880fed4c5..c766a8ce0 100644
--- a/app/controllers/users/dossiers/invites_controller.rb
+++ b/app/controllers/users/dossiers/invites_controller.rb
@@ -14,10 +14,8 @@ class Users::Dossiers::InvitesController < UsersController
 
     if @facade.dossier.brouillon?
       redirect_to brouillon_dossier_path(@facade.dossier)
-    elsif Flipflop.new_dossier_details?
-      return redirect_to dossier_path(@facade.dossier)
     else
-      render 'users/recapitulatif/show'
+      return redirect_to dossier_path(@facade.dossier)
     end
   rescue ActiveRecord::RecordNotFound
     flash.alert = t('errors.messages.dossier_not_found')
diff --git a/app/controllers/users/recapitulatif_controller.rb b/app/controllers/users/recapitulatif_controller.rb
index 85dea28af..4486e64d4 100644
--- a/app/controllers/users/recapitulatif_controller.rb
+++ b/app/controllers/users/recapitulatif_controller.rb
@@ -4,11 +4,7 @@ class Users::RecapitulatifController < UsersController
   end
 
   def show
-    if Flipflop.new_dossier_details?
-      redirect_to dossier_url(current_user_dossier)
-    else
-      create_dossier_facade
-    end
+    redirect_to dossier_url(current_user_dossier)
   end
 
   def initiate
diff --git a/app/helpers/dossier_helper.rb b/app/helpers/dossier_helper.rb
index 4e9367bb4..06a7001c9 100644
--- a/app/helpers/dossier_helper.rb
+++ b/app/helpers/dossier_helper.rb
@@ -18,10 +18,8 @@ module DossierHelper
   def url_for_dossier(dossier)
     if dossier.brouillon?
       brouillon_dossier_path(dossier)
-    elsif Flipflop.new_dossier_details?
-      dossier_path(dossier)
     else
-      users_dossier_recapitulatif_path(dossier)
+      dossier_path(dossier)
     end
   end
 
diff --git a/app/views/new_user/dossiers/_dossier_footer.html.haml b/app/views/new_user/dossiers/_dossier_footer.html.haml
index e94e44b4a..8c6f2d11f 100644
--- a/app/views/new_user/dossiers/_dossier_footer.html.haml
+++ b/app/views/new_user/dossiers/_dossier_footer.html.haml
@@ -20,10 +20,7 @@
               = link_to service.email, "mailto:#{service.email}"
             - else
               Directement
-              - if Flipflop.new_dossier_details?
-                = link_to "par la messagerie", messagerie_dossier_path(dossier)
-              - else
-                = link_to "par la messagerie", users_dossier_recapitulatif_path(dossier)
+              = link_to "par la messagerie", messagerie_dossier_path(dossier)
 
           %p
             Par téléphone :
diff --git a/app/views/new_user/dossiers/merci.html.haml b/app/views/new_user/dossiers/merci.html.haml
index d0fbc9a5a..7b6667e98 100644
--- a/app/views/new_user/dossiers/merci.html.haml
+++ b/app/views/new_user/dossiers/merci.html.haml
@@ -18,7 +18,4 @@
       %b échanger avec un instructeur
       lors de sa construction et de son instruction
 
-    - if Flipflop.new_dossier_details?
-      = link_to 'Accéder à votre dossier', dossier_path(@dossier), class: 'button large primary'
-    - else
-      = link_to 'Accéder à votre dossier', users_dossier_recapitulatif_path(@dossier), class: 'button large primary'
+    = link_to 'Accéder à votre dossier', dossier_path(@dossier), class: 'button large primary'
diff --git a/config/features.rb b/config/features.rb
index e9eb6c48d..fcc8384c7 100644
--- a/config/features.rb
+++ b/config/features.rb
@@ -19,10 +19,6 @@ Flipflop.configure do
   feature :publish_draft
   feature :support_form
 
-  feature :new_dossier_details,
-    title: "Nouvelle page « Dossier »",
-    default: true
-
   group :production do
     feature :remote_storage,
       default: ENV['FOG_ENABLED'] == 'enabled'
diff --git a/spec/controllers/new_user/dossiers_controller_spec.rb b/spec/controllers/new_user/dossiers_controller_spec.rb
index c7c60bcc6..352d56995 100644
--- a/spec/controllers/new_user/dossiers_controller_spec.rb
+++ b/spec/controllers/new_user/dossiers_controller_spec.rb
@@ -578,10 +578,7 @@ describe NewUser::DossiersController, type: :controller do
   end
 
   describe '#show' do
-    let(:new_dossier_details_enabled) { false }
-
     before do
-      Flipflop::FeatureSet.current.test!.switch!(:new_dossier_details, new_dossier_details_enabled)
       sign_in(user)
     end
 
@@ -594,17 +591,8 @@ describe NewUser::DossiersController, type: :controller do
 
     context 'when the dossier has been submitted' do
       let(:dossier) { create(:dossier, :en_construction, user: user) }
-
-      context 'and the new dossier details page is disabled' do
-        let(:new_dossier_details_enabled) { false }
-        it { is_expected.to redirect_to(users_dossier_recapitulatif_path(dossier)) }
-      end
-
-      context 'and the new dossier details page is enabled' do
-        let(:new_dossier_details_enabled) { true }
-        it { expect(assigns(:dossier)).to eq(dossier) }
-        it { is_expected.to render_template(:show) }
-      end
+      it { expect(assigns(:dossier)).to eq(dossier) }
+      it { is_expected.to render_template(:show) }
     end
   end
 
@@ -612,7 +600,6 @@ describe NewUser::DossiersController, type: :controller do
     let(:dossier) { create(:dossier, :en_construction, user: user) }
 
     before do
-      Flipflop::FeatureSet.current.test!.switch!(:new_dossier_details, true)
       sign_in(user)
     end
 
diff --git a/spec/features/new_user/dossier_details_spec.rb b/spec/features/new_user/dossier_details_spec.rb
index 61218f8be..cf99fed3d 100644
--- a/spec/features/new_user/dossier_details_spec.rb
+++ b/spec/features/new_user/dossier_details_spec.rb
@@ -6,7 +6,6 @@ describe 'Dossier details:' do
   let(:dossier) { create(:dossier, :en_construction, :for_individual, :with_commentaires, user: user, procedure: procedure) }
 
   before do
-    Flipflop::FeatureSet.current.test!.switch!(:new_dossier_details, true)
     visit_dossier dossier
   end
 
diff --git a/spec/features/new_user/invite_spec.rb b/spec/features/new_user/invite_spec.rb
index 70d3614f3..60b5cc0f7 100644
--- a/spec/features/new_user/invite_spec.rb
+++ b/spec/features/new_user/invite_spec.rb
@@ -75,10 +75,6 @@ feature 'Invitations' do
   context 'when the dossier is en_construction' do
     let!(:dossier) { create(:dossier, :for_individual, :en_construction, user: owner, procedure: procedure) }
 
-    before do
-      Flipflop::FeatureSet.current.test!.switch!(:new_dossier_details, true)
-    end
-
     scenario 'on dossier details, the owner of a dossier can invite another user to collaborate on the dossier', js: true do
       log_in(owner)
       navigate_to_dossier(dossier)
@@ -101,47 +97,6 @@ feature 'Invitations' do
     end
   end
 
-  context 'when the dossier is en_construction (legacy UI)' do
-    let!(:dossier) { create(:dossier, :for_individual, :en_construction, user: owner, procedure: procedure) }
-
-    before do
-      Flipflop::FeatureSet.current.test!.switch!(:new_dossier_details, false)
-    end
-
-    scenario 'on dossier details, a user can invite another user to collaborate on the dossier', js: true do
-      log_in(owner)
-      navigate_to_recapitulatif(dossier)
-
-      legacy_send_invite_to "user_invite@exemple.fr"
-
-      expect(page).to have_current_path(users_dossier_recapitulatif_path(dossier))
-      expect(page).to have_text("Une invitation a été envoyée à user_invite@exemple.fr.")
-      expect(page).to have_text("user_invite@exemple.fr")
-    end
-
-    scenario 'an invited user can see and edit the dossier', js: true do
-      visit users_dossiers_invite_path(invite)
-      expect(page).to have_current_path(new_user_session_path)
-
-      submit_login_form(invited_user.email, invited_user.password)
-      expect(page).to have_current_path(users_dossiers_invite_path(invite))
-      expect(page).to have_no_selector('.button.invite-user-action')
-      expect(page).to have_text("Dossier nº #{dossier.id}")
-
-      # We should be able to just click() the link, but Capybara detects that the
-      # enclosing div would be clicked instead.
-      expect(page).to have_link("MODIFIER", href: brouillon_dossier_path(dossier))
-      visit brouillon_dossier_path(dossier)
-
-      expect(page).to have_current_path(brouillon_dossier_path(dossier))
-      fill_in "Texte obligatoire", with: "Some edited value"
-      click_button "Enregistrer les modifications du dossier"
-
-      expect(page).to have_current_path(users_dossiers_invite_path(invite))
-      expect(page).to have_text("Some edited value")
-    end
-  end
-
   private
 
   def log_in(user)
@@ -175,12 +130,6 @@ feature 'Invitations' do
     submit_login_form(invited_user.email, invited_user.password)
   end
 
-  def navigate_to_recapitulatif(dossier)
-    expect(page).to have_current_path(dossiers_path)
-    click_on(dossier.id)
-    expect(page).to have_current_path(users_dossier_recapitulatif_path(dossier))
-  end
-
   def send_invite_to(invited_email)
     click_on "Inviter une personne à modifier ce dossier"
     expect(page).to have_button("Envoyer une invitation", visible: true)
@@ -188,15 +137,4 @@ feature 'Invitations' do
     fill_in 'invite_email', with: invited_email
     click_on "Envoyer une invitation"
   end
-
-  def legacy_send_invite_to(invited_email)
-    find('.dropdown-toggle', text: "Voir les personnes impliquées").click()
-    expect(page).to have_button("Ajouter", visible: true)
-
-    fill_in 'invite_email', with: invited_email
-
-    page.accept_alert "Envoyer l'invitation ?" do
-      click_on "Ajouter"
-    end
-  end
 end
diff --git a/spec/features/users/flux_de_commentaires_spec.rb b/spec/features/users/flux_de_commentaires_spec.rb
deleted file mode 100644
index 12b7ec552..000000000
--- a/spec/features/users/flux_de_commentaires_spec.rb
+++ /dev/null
@@ -1,28 +0,0 @@
-require 'spec_helper'
-
-feature 'users: flux de commentaires' do
-  let(:user) { create(:user) }
-  let(:dossier) { create(:dossier, :with_entreprise, user: user, state: Dossier.states.fetch(:en_construction)) }
-  let(:dossier_id) { dossier.id }
-
-  let(:champ1) { dossier.champs.first }
-  let(:champ2) { create(:champ, dossier: dossier, type_de_champ: create(:type_de_champ, libelle: "subtitle")) }
-
-  let!(:commentaire1) { create(:commentaire, dossier: dossier, champ: champ1) }
-  let!(:commentaire2) { create(:commentaire, dossier: dossier, email: 'paul.chavard@beta.gouv.fr') }
-  let!(:commentaire3) { create(:commentaire, dossier: dossier, champ: champ2) }
-  let!(:commentaire4) { create(:commentaire, dossier: dossier, champ: champ1) }
-
-  before do
-    Flipflop::FeatureSet.current.test!.switch!(:new_dossier_details, false)
-    login_as user, scope: :user
-    visit users_dossier_recapitulatif_path(dossier)
-  end
-
-  scenario "seuls les commentaires généraux sont affichés" do
-    comments = find(".commentaires")
-    expect(comments).to have_selector(".content", count: 1)
-    expect(comments).to have_content('paul.chavard')
-    expect(comments).not_to have_content('paul.chavard@beta.gouv.fr')
-  end
-end