Add e2e repro (#44656)

e2e/test/scenarios/joins/joins-reproductions.cy.spec.js

@@ -1111,3 +1111,27 @@ describe("issue 31769", () => {
       .should("exist");
   });
 });
+
+describe("issue 39448", () => {
+  beforeEach(() => {
+    restore();
+    cy.signInAsNormalUser();
+  });
+
+  it("should load joined table metadata for suggested join conditions (metabase#39448)", () => {
+    openOrdersTable({ mode: "notebook" });
+    cy.findByTestId("action-buttons").button("Join data").click();
+    entityPickerModal().within(() => {
+      entityPickerModalTab("Tables").click();
+      cy.findByText("Products").click();
+    });
+    getNotebookStep("join").within(() => {
+      cy.findByLabelText("Right table").should("have.text", "Products");
+      cy.findByLabelText("Left column")
+        .findByText("Product ID")
+        .should("be.visible");
+      cy.findByLabelText("Right column").findByText("ID").should("be.visible");
+      cy.findByLabelText("Change operator").should("have.text", "=");
+    });
+  });
+});