diff --git a/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/browser-smoke.mjs b/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/browser-smoke.mjs
index 560f7465..766a9400 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/browser-smoke.mjs
+++ b/src/trx-client/trx-frontend/trx-frontend-http/frontend/tests/browser-smoke.mjs
@@ -30,9 +30,28 @@ const rigItems = ["rig-a", "rig-b"].map((remote) => ({
 const rigsResponse = { rigs: rigItems, active_remote: "rig-a" };
 const selectedRigs = [];
 
+// A realistic decoder registry.  Serving an empty one hid most of the
+// application from this test: the decoder sub-tabs, their panels, the decode
+// toggles and the bookmark decoder checkboxes are all built from it, so with
+// no decoders only three of thirteen sub-tabs existed and none of the decoder
+// UI was ever constructed.
+const decoderRegistry = [
+  { id: "ft8", label: "FT8", activation: "toggle", active_modes: ["USB"] },
+  { id: "ft4", label: "FT4", activation: "toggle", active_modes: ["USB"] },
+  { id: "ft2", label: "FT2", activation: "toggle", active_modes: ["USB"] },
+  { id: "wspr", label: "WSPR", activation: "toggle", active_modes: ["USB"] },
+  { id: "cw", label: "CW", activation: "toggle", active_modes: ["CW", "CWR"] },
+  { id: "sat", label: "SAT", activation: "toggle", active_modes: ["FM"] },
+  { id: "wefax", label: "WEFAX", activation: "toggle", active_modes: ["USB"] },
+  { id: "ais", label: "AIS", activation: "toggle", active_modes: ["FM"] },
+  { id: "aprs", label: "APRS", activation: "toggle", active_modes: ["FM"] },
+  { id: "hf-aprs", label: "HF APRS", activation: "toggle", active_modes: ["USB"] },
+  { id: "vdes", label: "VDES", activation: "toggle", active_modes: ["FM"] },
+].map((decoder) => ({ ...decoder, background_decode: false, bookmark_selectable: true }));
+
 const jsonRoutes = new Map([
   ["/auth/session", { authenticated: true, role: "control", auth_disabled: true }],
-  ["/decoders", []],
+  ["/decoders", decoderRegistry],
   ["/rigs", rigsResponse],
   ["/status", {
     info: {