Forward Port of #37721 to master

addons/web/static/src/js/fields/relational_fields.js

@@ -901,14 +901,32 @@ var ListFieldMany2One = FieldMany2One.extend({
         this.m2oDialogFocused = false;
     },
     /**
-     * In list views, we don't want to try to trigger a fieldChange when the field
+     * In case the focus is lost from a mousedown, we want to prevent the click occuring on the
+     * following mouseup since it might trigger some unwanted list functions.
+     * If it's not the case, we want to remove the added handler on the next mousedown.
+     * @see list_editable_renderer._onWindowClicked()
+     *
+     * Also, in list views, we don't want to try to trigger a fieldChange when the field
      * is being emptied. Instead, it will be triggered as the user leaves the field
      * while it is empty.
      *
      * @override
      * @private
      */
     _onInputFocusout: function () {
+        if (this.can_create && this.floating) {
+            // In case the focus out is due to a mousedown, we want to prevent the next click
+            var attachedEvents = ['click', 'mousedown'];
+            var stopNextClick = (function (ev) {
+                ev.stopPropagation();
+                attachedEvents.forEach(function (eventName) {
+                    window.removeEventListener(eventName, stopNextClick, true);
+                });
+            }).bind(this);
+            attachedEvents.forEach(function (eventName) {
+                window.addEventListener(eventName, stopNextClick, true);
+            });
+        }
         this._super.apply(this, arguments);
         if (!this.m2oDialogFocused && this.$input.val() === "" && this.mustSetValue) {
             this.reinitialize(false);

addons/web/static/tests/views/list_tests.js

@@ -8258,6 +8258,36 @@ QUnit.module('Views', {
 
         list.destroy();
     });
+    QUnit.test("quickcreate in a many2one in a list", async function (assert) {
+        assert.expect(2);
+
+        const list = await createView({
+            arch: '<tree editable="top"><field name="m2o"/></tree>',
+            data: this.data,
+            model: 'foo',
+            View: ListView,
+        });
+
+        await testUtils.dom.click(list.$('.o_data_row:first .o_data_cell:first'));
+
+        const $input = list.$('.o_data_row:first .o_data_cell:first input');
+        await testUtils.fields.editInput($input, "aaa");
+        $input.trigger('keyup');
+        $input.trigger('blur');
+        document.body.click();
+
+        await testUtils.nextTick();
+
+        assert.containsOnce(document.body, '.modal', "the quick_create modal should appear");
+
+        await testUtils.dom.click($('.modal .btn-primary:first'));
+        await testUtils.dom.click(document.body);
+
+        assert.strictEqual(list.el.getElementsByClassName('o_data_cell')[0].innerHTML, "aaa",
+            "value should have been updated");
+
+        list.destroy();
+    });
 
     QUnit.test('float field render with digits attribute on listview', async function (assert) {
         assert.expect(1);