diff --git a/web_dialog_size/__manifest__.py b/web_dialog_size/__manifest__.py
index b074138b2..20ccc23eb 100644
--- a/web_dialog_size/__manifest__.py
+++ b/web_dialog_size/__manifest__.py
@@ -15,7 +15,7 @@
     "Odoo Community Association (OCA)",
     "website": "https://github.com/OCA/web",
     "category": "web",
-    "version": "15.0.1.0.1",
+    "version": "16.0.1.0.0",
     "license": "AGPL-3",
     "depends": ["web"],
     "installable": True,
@@ -25,8 +25,6 @@
             "/web_dialog_size/static/src/js/web_dialog_size.esm.js",
             "/web_dialog_size/static/src/js/web_dialog_draggable.esm.js",
             "/web_dialog_size/static/src/scss/web_dialog_size.scss",
-        ],
-        "web.assets_qweb": [
             "/web_dialog_size/static/src/xml/web_dialog_size.xml",
             "/web_dialog_size/static/src/xml/ExpandButton.xml",
             "/web_dialog_size/static/src/xml/DialogDraggable.xml",
diff --git a/web_dialog_size/readme/CONFIGURATION.rst b/web_dialog_size/readme/CONFIGURATION.rst
deleted file mode 100644
index 18b1ad078..000000000
--- a/web_dialog_size/readme/CONFIGURATION.rst
+++ /dev/null
@@ -1,3 +0,0 @@
-By default, the module respects the caller's ``dialog_size`` option.
-If you want to override this and have all dialogs maximized by default,
-set the configuration parameter ``web_dialog_size.default_maximize`` to ``1``.
diff --git a/web_dialog_size/readme/CONFIGURE.rst b/web_dialog_size/readme/CONFIGURE.rst
index 902f3316e..243ecce5a 100644
--- a/web_dialog_size/readme/CONFIGURE.rst
+++ b/web_dialog_size/readme/CONFIGURE.rst
@@ -1,3 +1,4 @@
+By default, the module respects the caller's ``dialog_size`` option.
 If you want to set dialog boxes maximized by default, you need to:
 
 #. Go to *Settings -> Technical -> Parameters -> System Parameters*
diff --git a/web_dialog_size/static/src/js/web_dialog_draggable.esm.js b/web_dialog_size/static/src/js/web_dialog_draggable.esm.js
index f47eae5fc..92ea85a35 100644
--- a/web_dialog_size/static/src/js/web_dialog_draggable.esm.js
+++ b/web_dialog_size/static/src/js/web_dialog_draggable.esm.js
@@ -1,19 +1,19 @@
 /** @odoo-module **/
 
-import {patch} from "@web/core/utils/patch";
+import {ActionDialog} from "@web/webclient/actions/action_dialog";
+import {onMounted, useExternalListener} from "@odoo/owl";
+import {useListener} from "@web/core/utils/hooks";
+import {LegacyComponent} from "@web/legacy/legacy_component";
 import {Dialog} from "@web/core/dialog/dialog";
-const {useExternalListener} = owl.hooks;
-import {useListener} from "web.custom_hooks";
-const {Component} = owl;
 
-export class DialogDraggable extends Component {
+export class DialogDraggable extends LegacyComponent {
     setup() {
         this.element_position = {x: 0, y: 0};
         this.mouse_to_element_ratio = {x: 0, y: 0};
         const bound_onDrag = this.onDrag.bind(this);
         useListener("mousedown", "header.modal-header", (event) => {
-            const y = parseInt(this.el.offsetTop, 10);
-            const x = parseInt(this.el.offsetLeft, 10);
+            const y = parseInt(this.el.querySelector(".modal-content").offsetTop, 10);
+            const x = parseInt(this.el.querySelector(".modal-content").offsetLeft, 10);
             this.mouse_to_element_ratio = {x: event.x - x, y: event.y - y};
             this.element_position = {
                 x: event.x - this.mouse_to_element_ratio.x - x,
@@ -24,11 +24,12 @@ export class DialogDraggable extends Component {
         useExternalListener(document, "mouseup", () =>
             document.removeEventListener("mousemove", bound_onDrag)
         );
+        onMounted(() => {
+            this.el.querySelector(".modal-content").classList.add("position-absolute");
+            this.el.parentNode.classList.add("position-relative");
+        });
     }
-    mounted() {
-        this.el.classList.add("position-absolute");
-        this.el.offsetParent.classList.add("position-relative");
-    }
+
     getMovePosition({x, y}) {
         return {
             x: x - this.mouse_to_element_ratio.x - this.element_position.x,
@@ -37,16 +38,13 @@ export class DialogDraggable extends Component {
     }
     onDrag(event) {
         const {x, y} = this.getMovePosition(event);
-        this.el.style.left = `${x}px`;
-        this.el.style.top = `${y}px`;
+        const el = this.el.querySelector(".modal-content");
+        el.style.left = `${x}px`;
+        el.style.top = `${y}px`;
     }
 }
 
 DialogDraggable.template = "DialogDraggable";
 
-patch(Dialog, "web_dialog_size.DialogDraggable", {
-    components: {
-        ...Dialog.components,
-        DialogDraggable,
-    },
-});
+Dialog.components = Object.assign(Dialog.components || {}, {DialogDraggable});
+Object.assign(ActionDialog.components, {DialogDraggable});
diff --git a/web_dialog_size/static/src/js/web_dialog_size.esm.js b/web_dialog_size/static/src/js/web_dialog_size.esm.js
index c3f5a083e..ae2a8c771 100644
--- a/web_dialog_size/static/src/js/web_dialog_size.esm.js
+++ b/web_dialog_size/static/src/js/web_dialog_size.esm.js
@@ -3,8 +3,9 @@
 import {ActionDialog} from "@web/webclient/actions/action_dialog";
 import {patch} from "@web/core/utils/patch";
 import rpc from "web.rpc";
-const {Component} = owl;
-const {onMounted} = owl.hooks;
+import {Component, onMounted} from "@odoo/owl";
+import {Dialog} from "@web/core/dialog/dialog";
+import {SelectCreateDialog} from "@web/views/view_dialogs/select_create_dialog";
 
 export class ExpandButton extends Component {
     setup() {
@@ -26,16 +27,18 @@ export class ExpandButton extends Component {
 
     dialog_button_extend() {
         this.props.setsize("dialog_full_screen");
+        this.render();
     }
 
     dialog_button_restore() {
         this.props.setsize(this.last_size);
+        this.render();
     }
 }
 
 ExpandButton.template = "web_dialog_size.ExpandButton";
 
-patch(ActionDialog.prototype, "web_dialog_size.ActionDialog", {
+patch(Dialog.prototype, "web_dialog_size.Dialog", {
     setup() {
         this._super(...arguments);
         this.setSize = this.setSize.bind(this);
@@ -43,18 +46,37 @@ patch(ActionDialog.prototype, "web_dialog_size.ActionDialog", {
     },
 
     setSize(size) {
-        this.size = size;
+        this.props.size = size;
         this.render();
     },
 
     getSize() {
-        return this.size;
+        return this.props.size;
     },
 });
 
-patch(ActionDialog, "web_dialog_size.ActionDialog", {
-    components: {
-        ...ActionDialog.components,
-        ExpandButton,
+patch(SelectCreateDialog.prototype, "web_dialog_size.SelectCreateDialog", {
+    setup() {
+        this._super(...arguments);
+        this.setSize = this.setSize.bind(this);
+        this.getSize = this.getSize.bind(this);
+    },
+
+    setSize(size) {
+        this.props.size = size;
+        this.render();
+    },
+
+    getSize() {
+        return this.props.size;
     },
 });
+
+Object.assign(ActionDialog.components, {ExpandButton});
+SelectCreateDialog.components = Object.assign(SelectCreateDialog.components || {}, {
+    ExpandButton,
+});
+Dialog.components = Object.assign(Dialog.components || {}, {ExpandButton});
+// Patch annoying validation method
+Dialog.props.size.validate = (s) =>
+    ["sm", "md", "lg", "xl", "dialog_full_screen"].includes(s);
diff --git a/web_dialog_size/static/src/scss/web_dialog_size.scss b/web_dialog_size/static/src/scss/web_dialog_size.scss
index abf3aba73..44e2066f1 100644
--- a/web_dialog_size/static/src/scss/web_dialog_size.scss
+++ b/web_dialog_size/static/src/scss/web_dialog_size.scss
@@ -1,24 +1,16 @@
 .modal {
-    .dialog_full_screen {
+    .modal-dialog_full_screen {
         @include media-breakpoint-up(sm) {
             max-width: 100%;
             width: calc(100% - 50px);
         }
     }
-    .modal-header button.close {
-        font-size: 18px;
 
-        &:not(.dialog_button_extend):not(.dialog_button_restore) {
-            @include media-breakpoint-up(sm) {
-                margin-left: 15px;
-            }
-        }
-
-        &.dialog_button_extend,
-        .dialog_button_restore {
-            @include media-breakpoint-down(sm) {
-                display: none !important;
-            }
+    .dialog_button_restore,
+    .dialog_button_extend {
+        margin-left: auto;
+        + .btn-close {
+            margin: -8px -8px -8px 0px;
         }
     }
 }
diff --git a/web_dialog_size/static/src/xml/DialogDraggable.xml b/web_dialog_size/static/src/xml/DialogDraggable.xml
index 6cafd8641..bc30ace1c 100644
--- a/web_dialog_size/static/src/xml/DialogDraggable.xml
+++ b/web_dialog_size/static/src/xml/DialogDraggable.xml
@@ -1,6 +1,8 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <templates>
     <t t-name="DialogDraggable" owl="1">
-        <t t-slot="default" />
+        <div>
+            <t t-slot="default" />
+        </div>
     </t>
 </templates>
diff --git a/web_dialog_size/static/src/xml/ExpandButton.xml b/web_dialog_size/static/src/xml/ExpandButton.xml
index 22318ef73..9544445b6 100644
--- a/web_dialog_size/static/src/xml/ExpandButton.xml
+++ b/web_dialog_size/static/src/xml/ExpandButton.xml
@@ -4,7 +4,7 @@
         <button
             t-if="props.getsize() == 'dialog_full_screen'"
             type="button"
-            class="close dialog_button_extend"
+            class="btn btn-secondary dialog_button_extend"
             t-on-click="dialog_button_restore"
         >
             <i class="fa fa-compress" />
@@ -12,7 +12,7 @@
         <button
             t-if="props.getsize() != 'dialog_full_screen'"
             type="button"
-            class="close dialog_button_restore"
+            class="btn btn-secondary dialog_button_restore"
             t-on-click="dialog_button_extend"
         >
             <i class="fa fa-expand" />
diff --git a/web_dialog_size/static/src/xml/web_dialog_size.xml b/web_dialog_size/static/src/xml/web_dialog_size.xml
index e7cc3a7b6..ce1e281b8 100644
--- a/web_dialog_size/static/src/xml/web_dialog_size.xml
+++ b/web_dialog_size/static/src/xml/web_dialog_size.xml
@@ -2,20 +2,38 @@
 <templates xml:space="preserve">
     <!-- This is for old Dialog template.
     Because Odoo haven't done every template to OWL. -->
-    <t t-extend="Dialog">
-        <t t-jquery="button.close" t-operation="inner">
+    <t t-extend="web.DialogWidget">
+        <t t-jquery="button.btn-close" t-operation="inner">
             <i class="fa fa-close" />
         </t>
-        <t t-jquery="button.close" t-operation="before">
-            <button type="button" class="dialog_button_extend close">
+        <t t-jquery="button.btn-close" t-operation="before">
+            <button type="button" class="dialog_button_extend btn btn-secondary">
                 <i class="fa fa-expand" />
             </button>
-            <button type="button" class="dialog_button_restore close">
+            <button type="button" class="dialog_button_restore btn btn-secondary">
                 <i class="fa fa-compress" />
             </button>
         </t>
     </t>
 
+    <t t-inherit="web.LegacyAdaptedActionDialog" t-inherit-mode="extension" owl="1">
+        <xpath expr="//div[hasclass('modal-content')]" position="before">
+            <DialogDraggable />
+        </xpath>
+        <DialogDraggable position="inside">
+            <xpath expr="//div[hasclass('modal-content')]" position="move" />
+        </DialogDraggable>
+    </t>
+
+    <t t-inherit="web.Dialog" t-inherit-mode="extension" owl="1">
+        <xpath expr="//div[hasclass('modal-content')]" position="before">
+            <DialogDraggable />
+        </xpath>
+        <DialogDraggable position="inside">
+            <xpath expr="//div[hasclass('modal-content')]" position="move" />
+        </DialogDraggable>
+    </t>
+
     <t t-inherit="web.ActionDialog" t-inherit-mode="extension" owl="1">
         <xpath expr="//div[hasclass('modal-content')]" position="before">
             <DialogDraggable />
@@ -23,8 +41,28 @@
         <DialogDraggable position="inside">
             <xpath expr="//div[hasclass('modal-content')]" position="move" />
         </DialogDraggable>
-        <xpath expr="//button[hasclass('close')]" position="before">
-            <ExpandButton getsize="getSize" setsize="setSize" />
+    </t>
+
+    <t t-inherit="web.ActionDialog.header" t-inherit-mode="extension" owl="1">
+        <xpath expr="//button[hasclass('btn-close')]" position="before">
+            <ExpandButton getsize="getSize" setsize="setSize" t-if="!isFullscreen" />
         </xpath>
     </t>
+
+    <t t-inherit="web.Dialog.header" t-inherit-mode="extension" owl="1">
+        <xpath expr="//button[hasclass('btn-close')]" position="before">
+            <ExpandButton
+                getsize="getSize"
+                setsize="setSize"
+                t-if="!isFullscreen and getSize and setSize"
+            />
+        </xpath>
+    </t>
+
+    <t t-inherit="web.SelectCreateDialog" t-inherit-mode="extension" owl="1">
+        <xpath expr="//Dialog" position="attributes">
+            <attribute name="size">props.size</attribute>
+        </xpath>
+    </t>
+
 </templates>