diff --git a/addons/partner_autocomplete/static/src/js/partner_autocomplete_core.js b/addons/partner_autocomplete/static/src/js/partner_autocomplete_core.js
index 1418c52d456..8831b9312b4 100644
--- a/addons/partner_autocomplete/static/src/js/partner_autocomplete_core.js
+++ b/addons/partner_autocomplete/static/src/js/partner_autocomplete_core.js
@@ -339,9 +339,8 @@ var PartnerAutocompleteMixin = {
             });
             self.displayNotification({
                 title,
-                message: content,
+                message: utils.Markup(content),
                 className: 'o_partner_autocomplete_no_credits_notify',
-                messageIsHtml: true, // the message is coming from a QWeb template using safe instructions
             });
         });
     },
@@ -360,9 +359,8 @@ var PartnerAutocompleteMixin = {
                 });
                 self.displayNotification({
                     title,
-                    message: content,
+                    message: utils.Markup(content),
                     className: 'o_partner_autocomplete_no_credits_notify',
-                    messageIsHtml: true, // the message is coming from a QWeb template using safe instructions
                 });
             }
             else {
diff --git a/addons/web/static/src/legacy/js/views/basic/basic_controller.js b/addons/web/static/src/legacy/js/views/basic/basic_controller.js
index 24daed9bcf7..356717500f3 100644
--- a/addons/web/static/src/legacy/js/views/basic/basic_controller.js
+++ b/addons/web/static/src/legacy/js/views/basic/basic_controller.js
@@ -11,6 +11,7 @@ var AbstractController = require('web.AbstractController');
 var core = require('web.core');
 var Dialog = require('web.Dialog');
 var FieldManagerMixin = require('web.FieldManagerMixin');
+var {Markup} = require('web.utils');
 var TranslationDialog = require('web.TranslationDialog');
 
 var _t = core._t;
@@ -592,9 +593,8 @@ var BasicController = AbstractController.extend(FieldManagerMixin, {
         warnings.push('</ul>');
         this.displayNotification({
             title: _t("Invalid fields:"),
-            message: warnings.join(''),
+            message: Markup(warnings.join('')),
             type: 'danger',
-            messageIsHtml: true, // dynamic parts of the message are escaped above
         });
     },
     /**
diff --git a/addons/web/static/src/legacy/js/widgets/attach_document.js b/addons/web/static/src/legacy/js/widgets/attach_document.js
index d84dcad9ac3..d206e2c8ac3 100644
--- a/addons/web/static/src/legacy/js/widgets/attach_document.js
+++ b/addons/web/static/src/legacy/js/widgets/attach_document.js
@@ -3,6 +3,7 @@ odoo.define('web.AttachDocument', function (require) {
 
 var core = require('web.core');
 var framework = require('web.framework');
+var {Markup} = require('web.utils');
 var widgetRegistry = require('web.widget_registry');
 var Widget = require('web.Widget');
 
@@ -64,9 +65,8 @@ var AttachDocument = Widget.extend({
         warnings.push('</ul>');
         this.displayNotification({
             title: _t("Invalid fields:"),
-            message: warnings.join(''),
+            message: Markup(warnings.join('')),
             type: 'danger',
-            messageIsHtml: true, // dynamic parts of the message are escaped above
         });
      },
 
diff --git a/addons/web/static/src/legacy/utils.js b/addons/web/static/src/legacy/utils.js
index 72ee1334671..af515c76bcb 100644
--- a/addons/web/static/src/legacy/utils.js
+++ b/addons/web/static/src/legacy/utils.js
@@ -211,7 +211,6 @@ export function makeLegacyNotificationService(legacyEnv) {
                 type,
                 className,
                 onClose,
-                messageIsHtml,
             }) {
                 if (subtitle) {
                     title = [title, subtitle].filter(Boolean).join(" ");
@@ -230,14 +229,14 @@ export function makeLegacyNotificationService(legacyEnv) {
                     };
                 });
 
-                const removeFn = env.services.notification.add(message, {
+                const removeFn = env.services.notification.add(_.escape(message), {
                     sticky,
                     title,
                     type,
                     className,
                     onClose,
                     buttons,
-                    messageIsHtml,
+                    messageIsHtml: true,
                 });
                 const id = ++notifId;
                 idsToRemoveFn[id] = removeFn;
diff --git a/addons/web/static/tests/legacy/fields/basic_fields_tests.js b/addons/web/static/tests/legacy/fields/basic_fields_tests.js
index 0e529cdb985..1c289277fb5 100644
--- a/addons/web/static/tests/legacy/fields/basic_fields_tests.js
+++ b/addons/web/static/tests/legacy/fields/basic_fields_tests.js
@@ -3923,7 +3923,7 @@ QUnit.module('basic_fields', {
                     if (ev.data.service === 'notification') {
                         assert.strictEqual(ev.data.method, 'notify');
                         assert.strictEqual(ev.data.args[0].title, 'Invalid fields:');
-                        assert.strictEqual(ev.data.args[0].message, '<ul><li>A date</li></ul>');
+                        assert.strictEqual(ev.data.args[0].message.toString(), '<ul><li>A date</li></ul>');
                     }
                 }
             },
@@ -6102,7 +6102,7 @@ QUnit.module('basic_fields', {
                     if (ev.data.service === 'notification') {
                         assert.strictEqual(ev.data.method, 'notify');
                         assert.strictEqual(ev.data.args[0].title, 'Invalid fields:');
-                        assert.strictEqual(ev.data.args[0].message, '<ul><li>Qux</li></ul>');
+                        assert.strictEqual(ev.data.args[0].message.toString(), '<ul><li>Qux</li></ul>');
                     }
                 }
             },
diff --git a/addons/web/static/tests/legacy/views/form_tests.js b/addons/web/static/tests/legacy/views/form_tests.js
index cf9b2b61b77..a400a034ac4 100644
--- a/addons/web/static/tests/legacy/views/form_tests.js
+++ b/addons/web/static/tests/legacy/views/form_tests.js
@@ -3664,7 +3664,7 @@ QUnit.module('Views', {
                         }
                         assert.strictEqual(params.title, 'Invalid fields:',
                             "should have a warning with correct title");
-                        assert.strictEqual(params.message, '<ul><li>Foo</li></ul>',
+                        assert.strictEqual(params.message.toString(), '<ul><li>Foo</li></ul>',
                             "should have a warning with correct message");
                     }
                 },
diff --git a/addons/web_editor/static/src/js/editor/snippets.editor.js b/addons/web_editor/static/src/js/editor/snippets.editor.js
index c9a9a4634bc..07c4d9e7b81 100644
--- a/addons/web_editor/static/src/js/editor/snippets.editor.js
+++ b/addons/web_editor/static/src/js/editor/snippets.editor.js
@@ -5,6 +5,7 @@ var concurrency = require('web.concurrency');
 var core = require('web.core');
 var Dialog = require('web.Dialog');
 var dom = require('web.dom');
+const {Markup, sprintf} = require('web.utils');
 var Widget = require('web.Widget');
 var options = require('web_editor.snippets.options');
 const {ColorPaletteWidget} = require('web_editor.ColorPalette');
@@ -2778,11 +2779,11 @@ var SnippetsMenu = Widget.extend({
                     }).guardedCatch(reason => {
                         reason.event.preventDefault();
                         this.close();
+                        const message = sprintf(Markup(_t("Could not install module <strong>%s</strong>")), name);
                         self.displayNotification({
-                            message: _.str.sprintf(_t("Could not install module <strong>%s</strong>"), owl.utils.escape(name)),
+                            message: message,
                             type: 'danger',
                             sticky: true,
-                            messageIsHtml: true, // dynamic parts of the message are escaped above
                         });
                     });
                 },
diff --git a/addons/web_editor/static/tests/field_html_tests.js b/addons/web_editor/static/tests/field_html_tests.js
index 18f3cd32ea5..7450d72ba19 100644
--- a/addons/web_editor/static/tests/field_html_tests.js
+++ b/addons/web_editor/static/tests/field_html_tests.js
@@ -198,7 +198,7 @@ QUnit.module('web_editor', {}, function () {
         });
 
         QUnit.test('check if required field is set', async function (assert) {
-            assert.expect(1);
+            assert.expect(3);
 
             var form = await testUtils.createView({
                 View: FormView,
@@ -212,12 +212,9 @@ QUnit.module('web_editor', {}, function () {
 
             testUtils.mock.intercept(form, 'call_service', function (ev) {
                 if (ev.data.service === 'notification') {
-                    assert.deepEqual(ev.data.args[0], {
-                        "message": "<ul><li>Header</li></ul>",
-                        "messageIsHtml": true,
-                        "title": "Invalid fields:",
-                        "type": "danger"
-                    });
+                    assert.strictEqual(ev.data.args[0].title, 'Invalid fields:');
+                    assert.strictEqual(ev.data.args[0].message.toString(), '<ul><li>Header</li></ul>');
+                    assert.strictEqual(ev.data.args[0].type, 'danger');
                 }
             }, true);
 
diff --git a/addons/website/static/src/js/content/website_root.js b/addons/website/static/src/js/content/website_root.js
index a7710edb095..987b04d2e47 100644
--- a/addons/website/static/src/js/content/website_root.js
+++ b/addons/website/static/src/js/content/website_root.js
@@ -3,6 +3,7 @@
 import ajax from 'web.ajax';
 import { _t } from 'web.core';
 import KeyboardNavigationMixin from 'web.KeyboardNavigationMixin';
+import {Markup} from 'web.utils';
 import session from 'web.session';
 import publicRootData from 'web.public.root';
 import "web.zoomodoo";
@@ -146,19 +147,16 @@ export const WebsiteRoot = publicRootData.PublicRoot.extend(KeyboardNavigationMi
 
                 if (!key) {
                     if (!editableMode && session.is_admin) {
+                        const message = _t("Cannot load google map.");
+                        const urlTitle = _t("Check your configuration.");
                         this.displayNotification({
                             type: 'warning',
                             sticky: true,
                             message:
-                                $('<div/>').append(
-                                    $('<span/>', {text: _t("Cannot load google map.")}),
-                                    $('<br/>'),
-                                    $('<a/>', {
-                                        href: "/web#action=website.action_website_configuration",
-                                        text: _t("Check your configuration."),
-                                    }),
-                                )[0].outerHTML,
-                            messageIsHtml: true, // HTML is built with only safe static parts
+                                Markup`<div>
+                                    <span>${message}</span><br/>
+                                    <a href="/web#action=website.action_website_configuration">${urlTitle}</a>
+                                </div>`,
                         });
                     }
                     resolve(false);
diff --git a/addons/website/static/src/js/editor/snippets.options.js b/addons/website/static/src/js/editor/snippets.options.js
index bbed1a84b91..2415535bdb7 100644
--- a/addons/website/static/src/js/editor/snippets.options.js
+++ b/addons/website/static/src/js/editor/snippets.options.js
@@ -6,6 +6,7 @@ const {ColorpickerWidget} = require('web.Colorpicker');
 const config = require('web.config');
 var core = require('web.core');
 var Dialog = require('web.Dialog');
+const {Markup, sprintf} = require('web.utils');
 const weUtils = require('web_editor.utils');
 var options = require('web_editor.snippets.options');
 const wLinkPopoverWidget = require('@website/js/widgets/link_popover_widget')[Symbol.for("default")];
@@ -2188,11 +2189,11 @@ options.registry.anchor = options.Class.extend({
         const clipboard = new ClipboardJS(this.$button[0], {text: () => this._getAnchorLink()});
         clipboard.on('success', () => {
             const anchor = decodeURIComponent(this._getAnchorLink());
+            const message = sprintf(Markup(_t("Anchor copied to clipboard<br>Link: %s")), anchor);
             this.displayNotification({
               type: 'success',
-              message: _.str.sprintf(_t("Anchor copied to clipboard<br>Link: %s"), owl.utils.escape(anchor)),
+              message: message,
               buttons: [{text: _t("Edit"), click: () => this.openAnchorDialog(), primary: true}],
-              messageIsHtml: true, // dynamic parts of the message are escaped above
             });
         });
 
diff --git a/addons/website_event/static/src/js/register_toaster_widget.js b/addons/website_event/static/src/js/register_toaster_widget.js
index 798e484abe6..fd2f944c78d 100644
--- a/addons/website_event/static/src/js/register_toaster_widget.js
+++ b/addons/website_event/static/src/js/register_toaster_widget.js
@@ -2,6 +2,7 @@ odoo.define('website_event.register_toaster_widget', function (require) {
 'use strict';
 
 let core = require('web.core');
+const {Markup} = require('web.utils');
 let _t = core._t;
 let publicWidget = require('web.public.widget');
 
@@ -18,9 +19,8 @@ publicWidget.registry.RegisterToasterWidget = publicWidget.Widget.extend({
         if (message && message.length) {
             this.displayNotification({
                 title: _t("Register"),
-                message: message,
+                message: Markup(message),
                 type: 'info',
-                messageIsHtml: true, // the message is coming from a QWeb template using safe instructions
             });
         }
         return this._super.apply(this, arguments);
diff --git a/addons/website_slides_survey/static/src/js/slides_certification_upload_toast.js b/addons/website_slides_survey/static/src/js/slides_certification_upload_toast.js
index 03775f68d8c..519af24a4b0 100644
--- a/addons/website_slides_survey/static/src/js/slides_certification_upload_toast.js
+++ b/addons/website_slides_survey/static/src/js/slides_certification_upload_toast.js
@@ -2,6 +2,7 @@ odoo.define('website_slides_survey.certification_upload_toast', function (requir
 'use strict';
 
 var publicWidget = require('web.public.widget');
+var {Markup, sprintf} = require('web.utils');
 
 var sessionStorage = window.sessionStorage;
 var core = require('web.core');
@@ -19,15 +20,13 @@ publicWidget.registry.CertificationUploadToast = publicWidget.Widget.extend({
         this._super.apply(this, arguments).then(function () {
             var url = sessionStorage.getItem("survey_certification_url");
             if (url) {
+                var message = sprintf(Markup(
+                    _t('Follow this link to add questions to your certification. <a href="%s">Edit certification</a>')), url);
                 self.displayNotification({
                     type: 'info',
                     title: _t('Certification created'),
-                    message: _.str.sprintf(
-                        _t('Follow this link to add questions to your certification. <a href="%s">Edit certification</a>'),
-                        _.escape(url)
-                    ),
+                    message: message,
                     sticky: true,
-                    messageIsHtml: true, // dynamic parts of the message are escaped above
                 });
                 sessionStorage.removeItem("survey_certification_url");
             }