diff --git a/addons/web/static/src/views/fields/relational_utils.js b/addons/web/static/src/views/fields/relational_utils.js
index 585cc222ac9..68d0038adc8 100644
--- a/addons/web/static/src/views/fields/relational_utils.js
+++ b/addons/web/static/src/views/fields/relational_utils.js
@@ -558,7 +558,10 @@ async function getFormViewInfo({ list, activeField, viewService, userService, en
             views: [[false, "form"]],
         });
         const archInfo = new FormArchParser().parse(views.form.arch, relatedModels, comodel);
-        formViewInfo = { ...archInfo, fields }; // should be good to memorize this on activeField
+        // Fields that need to be defined are the ones in the form view, this is natural,
+        // plus the ones that the list record has, that is, present in either the list arch or the kanban arch
+        // of the one2many field
+        formViewInfo = { ...archInfo, fields: { ...list.fields, ...fields } }; // should be good to memorize this on activeField
     }
 
     await loadSubViews(
diff --git a/addons/web/static/tests/views/fields/one2many_field_tests.js b/addons/web/static/tests/views/fields/one2many_field_tests.js
index 9f4f2bf043a..ebabc21cea9 100644
--- a/addons/web/static/tests/views/fields/one2many_field_tests.js
+++ b/addons/web/static/tests/views/fields/one2many_field_tests.js
@@ -12500,4 +12500,57 @@ QUnit.module("Fields", (hooks) => {
         assert.hasAttrValue(target.querySelector(".o_dialog .o_form_button_save_new"), "disabled", undefined);
         assert.hasAttrValue(target.querySelector(".o_dialog .o_form_button_cancel"), "disabled", undefined);
     });
+
+    QUnit.test("field in list but not in fetched form", async function (assert) {
+        serverData.models.partner.fields.o2m = {
+            type: "one2many",
+            relation: "partner_type",
+            relation_field: "p_id",
+        };
+        serverData.models.partner_type.onchanges = {
+            display_name: (rec) => {
+                if (rec.display_name === "changed") {
+                    rec.color = 5;
+                }
+            },
+        };
+
+        serverData.models.partner_type.fields.p_id = { type: "many2one", relation: "partner" };
+        serverData.views = {
+            "partner_type,false,form": `<form><field name="display_name" /></form>`,
+        };
+
+        await makeView({
+            type: "form",
+            resModel: "partner",
+            serverData,
+            arch: `
+                <form>
+                    <field name="o2m">
+                        <tree>
+                            <field name="display_name"/>
+                            <field name="color" />
+                        </tree>
+                    </field>
+                </form>`,
+            mockRPC(route, args) {
+                assert.step(`${args.method}: ${args.model}`);
+            },
+        });
+
+        assert.verifySteps(["get_views: partner", "onchange: partner"]);
+        await click(target, ".o_field_x2many_list_row_add a");
+        assert.verifySteps(["get_views: partner_type", "onchange: partner_type"]);
+        await editInput(
+            target.querySelector(".modal"),
+            ".o_field_widget[name='display_name'] input",
+            "changed"
+        );
+        assert.verifySteps(["onchange: partner_type"]);
+        await click(target.querySelector(".modal .o_form_button_save"));
+        assert.strictEqual(target.querySelector(".o_data_row").textContent, "changed5");
+        await click(target, ".o_form_button_save");
+        assert.verifySteps(["create: partner", "read: partner", "read: partner_type"]);
+        assert.strictEqual(target.querySelector(".o_data_row").textContent, "changed5");
+    });
 });