diff --git a/addons/web/static/src/js/fields/relational_fields.js b/addons/web/static/src/js/fields/relational_fields.js
index f4677ac7190..432961bc0bf 100644
--- a/addons/web/static/src/js/fields/relational_fields.js
+++ b/addons/web/static/src/js/fields/relational_fields.js
@@ -2959,11 +2959,7 @@ var FieldSelection = AbstractField.extend({
                 style: disabled ? "display: none" : "",
             }));
         }
-        var value = this.value;
-        if (this.field.type === 'many2one' && value) {
-            value = value.data.id;
-        }
-        this.$el.val(JSON.stringify(value));
+        this.$el.val(JSON.stringify(this._getRawValue()));
     },
     /**
      * @override
@@ -2971,6 +2967,14 @@ var FieldSelection = AbstractField.extend({
      */
     _renderReadonly: function () {
         this.$el.empty().text(this._formatValue(this.value));
+        this.$el.attr('raw-value', this._getRawValue());
+    },
+    _getRawValue: function() {
+        var raw_value = this.value;
+        if (this.field.type === 'many2one' && raw_value) {
+            raw_value = raw_value.data.id;
+        }
+        return raw_value;
     },
     /**
      * @override
diff --git a/addons/web/static/tests/fields/relational_fields_tests.js b/addons/web/static/tests/fields/relational_fields_tests.js
index 56bb564880f..487e953003f 100644
--- a/addons/web/static/tests/fields/relational_fields_tests.js
+++ b/addons/web/static/tests/fields/relational_fields_tests.js
@@ -997,7 +997,7 @@ QUnit.module('relational_fields', {
     });
 
     QUnit.test('widget selection, edition and on many2one field', async function (assert) {
-        assert.expect(19);
+        assert.expect(21);
 
         this.data.partner.onchanges = {product_id: function () {}};
         this.data.partner.records[0].product_id = 37;
@@ -1024,10 +1024,14 @@ QUnit.module('relational_fields', {
         assert.containsNone(form.$('.o_form_view'), 'select');
         assert.strictEqual(form.$('.o_field_widget[name=product_id]').text(), 'xphone',
             "should have rendered the many2one field correctly");
+        assert.strictEqual(form.$('.o_field_widget[name=product_id]').attr('raw-value'), '37',
+            "should have set the raw-value attr for many2one field correctly");
         assert.strictEqual(form.$('.o_field_widget[name=trululu]').text(), '',
             "should have rendered the unset many2one field correctly");
         assert.strictEqual(form.$('.o_field_widget[name=color]').text(), 'Red',
             "should have rendered the selection field correctly");
+        assert.strictEqual(form.$('.o_field_widget[name=color]').attr('raw-value'), 'red',
+            "should have set the raw-value attr for selection field correctly");
 
         await testUtils.form.clickEdit(form);