diff --git a/app/assets/stylesheets/new_design/avis.scss b/app/assets/stylesheets/new_design/avis.scss
index 0217f3d76..42e7c354d 100644
--- a/app/assets/stylesheets/new_design/avis.scss
+++ b/app/assets/stylesheets/new_design/avis.scss
@@ -105,6 +105,10 @@
       margin-top: $default-padding;
     }
 
+    .answer-body p:not(:last-of-type) {
+      margin-bottom: $default-padding;
+    }
+
     .avis-icon {
       margin-right: $default-spacer;
     }
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 7551320aa..8ab881d8b 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -195,7 +195,7 @@ class ApplicationController < ActionController::Base
 
   def sentry_user
     user = logged_user
-    { id: user&.id, role: user&.class&.name || 'Guest' }.compact
+    { id: user ? "#{user.class.name}##{user.id}" : 'Guest' }
   end
 
   def sentry_config
@@ -205,6 +205,7 @@ class ApplicationController < ActionController::Base
       key: sentry[:client_key],
       enabled: sentry[:enabled],
       environment: sentry[:environment],
+      browser: { modern: browser.modern? },
       user: sentry_user
     }
   end
diff --git a/app/controllers/users/commencer_controller.rb b/app/controllers/users/commencer_controller.rb
index a20a009fe..9a16ee2aa 100644
--- a/app/controllers/users/commencer_controller.rb
+++ b/app/controllers/users/commencer_controller.rb
@@ -4,38 +4,39 @@ module Users
 
     def commencer
       @procedure = Procedure.publiees.find_by(path: params[:path])
-
-      if @procedure.blank?
-        flash.alert = "La démarche est inconnue, ou la création de nouveaux dossiers pour cette démarche est terminée."
-        return redirect_to root_path
-      end
+      return procedure_not_found if @procedure.blank?
 
       render 'commencer/show'
     end
 
     def commencer_test
       @procedure = Procedure.brouillons.find_by(path: params[:path])
-
-      if @procedure.blank?
-        flash.alert = "La démarche est inconnue, ou cette démarche n’est maintenant plus en test."
-        return redirect_to root_path
-      end
+      return procedure_not_found if @procedure.blank?
 
       render 'commencer/show'
     end
 
     def sign_in
-      store_user_location!
+      @procedure = Procedure.find_by(path: params[:path])
+      return procedure_not_found if @procedure.blank?
+
+      store_user_location!(@procedure)
       redirect_to new_user_session_path
     end
 
     def sign_up
-      store_user_location!
+      @procedure = Procedure.find_by(path: params[:path])
+      return procedure_not_found if @procedure.blank?
+
+      store_user_location!(@procedure)
       redirect_to new_user_registration_path
     end
 
     def france_connect
-      store_user_location!
+      @procedure = Procedure.find_by(path: params[:path])
+      return procedure_not_found if @procedure.blank?
+
+      store_user_location!(@procedure)
       redirect_to france_connect_particulier_path
     end
 
@@ -45,8 +46,21 @@ module Users
 
     private
 
-    def store_user_location!
+    def procedure_not_found
       procedure = Procedure.find_by(path: params[:path])
+
+      if procedure&.archivee?
+        flash.alert = t('errors.messages.procedure_archived')
+      elsif procedure&.publiee?
+        flash.alert = t('errors.messages.procedure_not_draft')
+      else
+        flash.alert = t('errors.messages.procedure_not_found')
+      end
+
+      return redirect_to root_path
+    end
+
+    def store_user_location!(procedure)
       store_location_for(:user, helpers.procedure_lien(procedure))
     end
   end
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 08565167f..91df7a137 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -60,6 +60,12 @@ module ApplicationHelper
     # rubocop:enable Rails/OutputSafety
   end
 
+  def show_element(selector)
+    # rubocop:disable Rails/OutputSafety
+    raw("document.querySelector('#{selector}').classList.remove('hidden');")
+    # rubocop:enable Rails/OutputSafety
+  end
+
   def disable_element(selector)
     # rubocop:disable Rails/OutputSafety
     raw("document.querySelector('#{selector}').disabled = true;")
diff --git a/app/javascript/shared/track/sentry.js b/app/javascript/shared/track/sentry.js
index 5c3bafc17..23410535a 100644
--- a/app/javascript/shared/track/sentry.js
+++ b/app/javascript/shared/track/sentry.js
@@ -1,14 +1,13 @@
 import * as Sentry from '@sentry/browser';
 
-const { key, enabled, user, environment } = gon.sentry || {};
+const { key, enabled, user, environment, browser } = gon.sentry || {};
 
 // We need to check for key presence here as we do not have a dsn for browser yet
 if (enabled && key) {
   Sentry.init({ dsn: key, environment });
 
-  if (user.email) {
-    Sentry.configureScope(scope => {
-      scope.setUser(user);
-    });
-  }
+  Sentry.configureScope(scope => {
+    scope.setUser(user);
+    scope.setExtra('browser', browser.modern ? 'modern' : 'legacy');
+  });
 }
diff --git a/app/views/gestionnaires/shared/avis/_list.html.haml b/app/views/gestionnaires/shared/avis/_list.html.haml
index 23acc5a0b..c5837aac5 100644
--- a/app/views/gestionnaires/shared/avis/_list.html.haml
+++ b/app/views/gestionnaires/shared/avis/_list.html.haml
@@ -29,4 +29,5 @@
                 - else
                   %span.waiting En attente de réponse
               = render partial: 'shared/piece_jointe/pj_link', locals: { object: avis, pj: avis.piece_justificative_file }
-              %p= avis.answer
+              .answer-body
+                = simple_format(avis.answer)
diff --git a/app/views/users/dossiers/purge_champ_piece_justificative.js.erb b/app/views/users/dossiers/purge_champ_piece_justificative.js.erb
index 0aae810ba..9d8807116 100644
--- a/app/views/users/dossiers/purge_champ_piece_justificative.js.erb
+++ b/app/views/users/dossiers/purge_champ_piece_justificative.js.erb
@@ -1,5 +1,3 @@
 <%= render_flash(timeout: 5000, sticky: true) %>
 <%= remove_element("#piece_justificative_#{@champ.id}") %>
-
-let fileInputSelector = '<%= "#champs_#{@champ.id}" %>';
-document.querySelector(fileInputSelector).classList.remove('hidden');
+<%= show_element("#champs_#{@champ.id}") %>
diff --git a/config/locales/fr.yml b/config/locales/fr.yml
index f1a446173..c7aa81890 100644
--- a/config/locales/fr.yml
+++ b/config/locales/fr.yml
@@ -188,6 +188,7 @@ fr:
         connexion: "Erreur lors de la connexion à France Connect."
       extension_white_list_error: "Le format de fichier de la pièce jointe n'est pas valide."
       procedure_archived: "Cette démarche en ligne a été fermée, il n'est plus possible de déposer de dossier."
+      procedure_not_draft: "Cette démarche n’est maintenant plus en brouillon."
       cadastres_empty:
         one: "Aucune parcelle cadastrale sur la zone séléctionnée"
         other: "Aucune parcelle cadastrale sur les zones séléctionnées"
diff --git a/spec/controllers/application_controller_spec.rb b/spec/controllers/application_controller_spec.rb
index f07bd8737..d8070743d 100644
--- a/spec/controllers/application_controller_spec.rb
+++ b/spec/controllers/application_controller_spec.rb
@@ -34,7 +34,7 @@ describe ApplicationController, type: :controller do
     context 'when no one is logged in' do
       it do
         expect(Raven).to have_received(:user_context)
-          .with({ role: 'Guest' })
+          .with({ id: 'Guest' })
       end
 
       it do
@@ -53,7 +53,7 @@ describe ApplicationController, type: :controller do
 
       it do
         expect(Raven).to have_received(:user_context)
-          .with({ id: current_user.id, role: 'User' })
+          .with({ id: "User##{current_user.id}" })
       end
 
       it do
@@ -77,7 +77,7 @@ describe ApplicationController, type: :controller do
 
       it do
         expect(Raven).to have_received(:user_context)
-          .with({ id: current_user.id, role: 'User' })
+          .with({ id: "User##{current_user.id}" })
       end
 
       it do
diff --git a/spec/controllers/users/commencer_controller_spec.rb b/spec/controllers/users/commencer_controller_spec.rb
index ae8f2d01a..539cfaa7c 100644
--- a/spec/controllers/users/commencer_controller_spec.rb
+++ b/spec/controllers/users/commencer_controller_spec.rb
@@ -87,6 +87,14 @@ describe Users::CommencerController, type: :controller do
 
       it { expect(subject).to redirect_to(new_user_session_path) }
     end
+
+    context 'when the path doesn’t exist' do
+      subject { get :sign_in, params: { path: 'hello' } }
+
+      it 'redirects with an error message' do
+        expect(subject).to redirect_to(root_path)
+      end
+    end
   end
 
   describe '#sign_up' do
@@ -111,6 +119,14 @@ describe Users::CommencerController, type: :controller do
 
       it { expect(subject).to redirect_to(new_user_registration_path) }
     end
+
+    context 'when the path doesn’t exist' do
+      subject { get :sign_up, params: { path: 'hello' } }
+
+      it 'redirects with an error message' do
+        expect(subject).to redirect_to(root_path)
+      end
+    end
   end
 
   describe '#france_connect' do
@@ -135,5 +151,13 @@ describe Users::CommencerController, type: :controller do
 
       it { expect(subject).to redirect_to(france_connect_particulier_path) }
     end
+
+    context 'when the path doesn’t exist' do
+      subject { get :france_connect, params: { path: 'hello' } }
+
+      it 'redirects with an error message' do
+        expect(subject).to redirect_to(root_path)
+      end
+    end
   end
 end
diff --git a/spec/factories/avis.rb b/spec/factories/avis.rb
index 97abb989b..b7f4f556e 100644
--- a/spec/factories/avis.rb
+++ b/spec/factories/avis.rb
@@ -19,5 +19,9 @@ FactoryBot.define do
         avis.claimant = create :gestionnaire
       end
     end
+
+    trait :with_answer do
+      answer { "Mon avis se décompose en deux points :\n- La demande semble pertinente\n- Le demandeur remplit les conditions." }
+    end
   end
 end
diff --git a/spec/views/gestionnaire/shared/avis/list.html.haml_spec.rb b/spec/views/gestionnaire/shared/avis/list.html.haml_spec.rb
index 1f8797785..d8abdcbe8 100644
--- a/spec/views/gestionnaire/shared/avis/list.html.haml_spec.rb
+++ b/spec/views/gestionnaire/shared/avis/list.html.haml_spec.rb
@@ -1,3 +1,5 @@
+require 'spec_helper'
+
 describe 'gestionnaires/shared/avis/_list.html.haml', type: :view do
   before { view.extend DossierHelper }
 
@@ -5,16 +7,22 @@ describe 'gestionnaires/shared/avis/_list.html.haml', type: :view do
 
   let(:gestionnaire) { create(:gestionnaire) }
   let(:avis) { [create(:avis, claimant: gestionnaire)] }
+  let(:seen_at) { avis.first.created_at + 1.hour }
 
-  context "with a seen_at after avis created_at" do
-    let(:seen_at) { avis.first.created_at + 1.hour }
+  it { is_expected.to have_text(avis.first.introduction) }
+  it { is_expected.not_to have_css(".highlighted") }
 
-    it { is_expected.not_to have_css(".highlighted") }
-  end
-
-  context "with a seen_at after avis created_at" do
+  context 'with a seen_at before avis created_at' do
     let(:seen_at) { avis.first.created_at - 1.hour }
 
     it { is_expected.to have_css(".highlighted") }
   end
+
+  context 'with an answer' do
+    let(:avis) { [create(:avis, :with_answer, claimant: gestionnaire)] }
+
+    it 'renders the answer formatted with newlines' do
+      expect(subject).to include(simple_format(avis.first.answer))
+    end
+  end
 end