diff --git a/docs/support-matrix.md b/docs/support-matrix.md
index a8c1704..7e20b82 100644
--- a/docs/support-matrix.md
+++ b/docs/support-matrix.md
@@ -21,11 +21,11 @@ as with Python Breps.
 
 ## Commands
 
-| Status              | Commands                                                                                                                        |
-| ------------------- | ------------------------------------------------------------------------------------------------------------------------------- |
-| Included            | Basic materials and lights, scene and theme settings, UI controls, text tags, metadata, object actions, removal, and visibility |
-| Included callbacks  | Object picking, UI actions, object actions, loaded JSON, and custom host actions                                                |
-| Deferred or limited | Spinner, text geometry fonts, advanced physical-material options, Sky, and RectAreaLight                                        |
+| Status              | Commands                                                                                                                                 |
+| ------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
+| Included            | Basic materials and lights, scene and theme settings, UI controls, text tags, metadata, object actions, removal, visibility, and spinner |
+| Included callbacks  | Object picking, UI actions, object actions, loaded JSON, and custom host actions                                                         |
+| Deferred or limited | Text geometry fonts, advanced physical-material options, Sky, and RectAreaLight                                                          |
 
 Python-to-browser commands use binary protobuf envelopes. Browser-to-Python
 callbacks use JSON text.
diff --git a/src/App.vue b/src/App.vue
index 443fb1e..f070c42 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -5,6 +5,8 @@
     <Sidebar :show-toolbar="props.showToolbar" />
     <div ref="threeContainer" class="three-container"></div>
     <ThemeIndicator />
+    <ObjectInfo />
+    <GlobalSpinner />
     <RightSidebar />
   </div>
 </template>
@@ -14,6 +16,7 @@ import { onMounted, ref } from "vue";
 import RightSidebar from "./components/layout/RightSidebar.vue";
 import Sidebar from "@/components/layout/Sidebar.vue";
 import ThemeIndicator from "@/components/layout/ThemeIndicator.vue";
+import GlobalSpinner from "@/components/layout/GlobalSpinner.vue";
 import type { ViewerRuntime } from "@/viewer/viewer_runtime";
 
 const threeContainer = ref<HTMLDivElement | null>(null);
diff --git a/src/components/layout/GlobalSpinner.vue b/src/components/layout/GlobalSpinner.vue
new file mode 100644
index 0000000..80ccff1
--- /dev/null
+++ b/src/components/layout/GlobalSpinner.vue
@@ -0,0 +1,299 @@
+<template>
+  <Teleport to="body">
+    <div v-if="spinnerState.visible" class="global-spinner-overlay theme">
+      <LoaderCircle
+        class="global-spinner-icon"
+        :size="96"
+        :stroke-width="1.5"
+      />
+      <p v-if="spinnerState.message" class="global-spinner-official-text">
+        {{ spinnerState.message }}
+      </p>
+      <p v-if="funnyMessage" class="global-spinner-funny-text">
+        {{ funnyMessage }}
+      </p>
+    </div>
+  </Teleport>
+</template>
+
+<script setup lang="ts">
+import { ref, watch, onUnmounted } from "vue";
+import { LoaderCircle } from "lucide-vue-next";
+import { useViewerRuntime } from "@/viewer/viewer_context";
+
+const { spinnerState } = useViewerRuntime().store;
+
+const FUNNY_MESSAGES = [
+  "Consulting the geometry gods...",
+  "Asking the algorithm to calm down...",
+  "Convincing the computer this is intentional...",
+  "Counting things that probably don't need counting...",
+  "Making the polygons behave...",
+  "Untangling the spaghetti geometry...",
+  "Teaching vectors where to go...",
+  "Rotating things until they look right...",
+  "Checking if reality is still running...",
+  "Loading an unreasonable amount of geometry...",
+  "Negotiating with the CPU...",
+  "Blaming the mesh...",
+  "Adding more RAM, spiritually...",
+  "Making the triangles feel useful...",
+  "Convincing the vertices to cooperate...",
+  "Searching for the missing dimension...",
+  "Performing computational wizardry...",
+  "Sacrificing a GPU to the algorithm...",
+  "Asking the mesh nicely to be manifold...",
+  "Counting polygons instead of sheep...",
+  "Turning mathematics into architecture...",
+  "Turning architecture back into mathematics...",
+  "Making the computer question its life choices...",
+  "Checking whether this is actually a good idea...",
+  "Running several questionable calculations...",
+  "Applying advanced computational nonsense...",
+  "Removing unnecessary complexity by adding complexity...",
+  "Optimizing absolutely everything...",
+  "Optimizing something that was already fast...",
+  "Adding one more iteration...",
+  "Just one more iteration...",
+  "Okay, definitely the last iteration...",
+  "Pretending this will converge...",
+  "Waiting for convergence...",
+  "Negotiating with infinity...",
+  "Rounding numbers until they behave...",
+  "Arguing with floating-point arithmetic...",
+  "Trying to remember where we put zero...",
+  "Locating the origin...",
+  "Checking which way is up...",
+  "Verifying that 3D is still 3D...",
+  "Flattening things that should not be flattened...",
+  "Unflattening things that definitely should be flattened...",
+  "Making topology someone else's problem...",
+  "Searching for non-manifold nonsense...",
+  "Resolving existential intersections...",
+  "Making surfaces understand boundaries...",
+  "Asking the normals to face the right way...",
+  "Flipping normals and pretending nothing happened...",
+  "Meshing reality...",
+  "Remeshing reality...",
+  "Discretizing the universe...",
+  "Approximating perfection...",
+  "Generating controlled chaos...",
+  "Adding a little more randomness...",
+  "Removing suspicious randomness...",
+  "Randomizing the deterministic process...",
+  "Making deterministic randomness...",
+  "Running the forbidden loop...",
+  "Entering the computational abyss...",
+  "Checking what broke this time...",
+  "Finding the bug we introduced 20 minutes ago...",
+  "Looking for a missing comma...",
+  "Blaming JavaScript...",
+  "Blaming Python...",
+  "Blaming the GPU...",
+  "Blaming the user...",
+  "The computer knows what it did...",
+  "Have you tried turning the geometry off and on again?",
+  "Clearing the cache and our conscience...",
+  "Compiling some questionable decisions...",
+  "Waiting for the algorithm to have an idea...",
+  "Giving the CPU a moment to think...",
+  "Making the fans spin faster...",
+  "Converting electricity into polygons...",
+  "Converting polygons into more polygons...",
+  "Generating geometry nobody asked for...",
+  "Making unnecessary things parametric...",
+  "Parametrizing the obvious...",
+  "Overengineering a perfectly simple problem...",
+  "Adding another slider...",
+  "Adding sliders until it works...",
+  "Searching for the optimal number of sliders...",
+  "Making everything adjustable...",
+  "Making nothing adjustable...",
+  "Pretending the constraints are reasonable...",
+  "Negotiating with the constraints...",
+  "Relaxing the constraints...",
+  "Tightening the constraints...",
+  "Breaking the constraints...",
+  "Calling it a feature...",
+  "Calling it emergent behavior...",
+  "Calling it computational design...",
+  "Calling it architecture...",
+  "Generating plausible geometry...",
+  "Generating implausible geometry...",
+  "Making beautiful mistakes...",
+  "Turning mistakes into features...",
+  "Turning features into bugs...",
+  "Turning bugs into research...",
+  "Turning research into more bugs...",
+  "Approaching enlightenment...",
+  "Approaching the solution...",
+  "Approaching the deadline...",
+  "Running at 99% confidence...",
+  "Calculating with questionable precision...",
+  "Measuring things very precisely for no reason...",
+  "Checking if 90° is still 90°...",
+  "Making sure left is still left...",
+  "Making sure up is still up...",
+  "Checking whether the dimensions agree...",
+  "Synchronizing the coordinate systems...",
+  "Convincing coordinate systems to get along...",
+  "Finding the center of everything...",
+  "Locating the important point...",
+  "Calculating the least important point...",
+  "Interpolating between bad decisions...",
+  "Extrapolating beyond our expertise...",
+  "Projecting our problems onto a surface...",
+  "Solving problems in higher dimensions...",
+  "Bringing everything back to 3D...",
+  "Reducing dimensional existential dread...",
+  "Applying unnecessary mathematics...",
+  "Applying necessary mathematics reluctantly...",
+  "Doing linear algebra so you don't have to...",
+  "Multiplying matrices aggressively...",
+  "Taking the dot product personally...",
+  "Crossing our fingers and our vectors...",
+  "Normalizing everything...",
+  "Checking the normals...",
+  "Uniting the vectors...",
+  "Dividing by something suspicious...",
+  "Avoiding division by zero...",
+  "Negotiating with NaN...",
+  "Convincing infinity to come back down...",
+  "Removing NaNs from polite society...",
+  "Hunting floating-point errors...",
+  "Rounding things irresponsibly...",
+  "Preserving numerical dignity...",
+  "Running finite coffee analysis...",
+  "Calculating the optimal coffee break...",
+  "Optimizing caffeine throughput...",
+  "Loading structural optimism...",
+  "Generating computational optimism...",
+  "Waiting for inspiration to compile...",
+  "Compiling inspiration...",
+  "Downloading more geometry...",
+  "Downloading additional dimensions...",
+  "Searching the internet for more RAM...",
+  "Consulting the documentation we should have read earlier...",
+  "Reading error messages very carefully...",
+  "Ignoring the error message...",
+  "Re-reading the error message...",
+  "Accepting our fate...",
+  "Almost there...",
+  "Definitely almost there...",
+  "Probably almost there...",
+  "This is taking longer than expected...",
+  "Doing something extremely important...",
+  "Doing something extremely computational...",
+  "Please remain geometrically calm...",
+  "Please do not touch anything...",
+  "Everything is under control...",
+  "Everything was under control...",
+  "Nothing to see here...",
+  "This is completely normal...",
+  "Trusting the process...",
+  "Trusting the algorithm...",
+  "Questioning the process...",
+  "Questioning the algorithm...",
+  "Reconsidering our life choices...",
+  "Adding more computational violence...",
+  "Brute-forcing elegance...",
+  "Searching for elegance...",
+  "Giving up on elegance...",
+  "Embracing chaos...",
+  "Rendering the consequences...",
+  "Calculating the consequences...",
+  "Preparing the consequences...",
+  "Generating something probably useful...",
+  "Turning pixels into problems...",
+  "Turning problems into pixels...",
+  "Making computers do architecture...",
+  "Making architecture do mathematics...",
+  "Making mathematics do the heavy lifting...",
+  "Almost done. Probably.",
+];
+
+const funnyMessage = ref<string | null>(null);
+let messageInterval: ReturnType<typeof setInterval> | null = null;
+
+function pickFunnyMessage(): string {
+  return FUNNY_MESSAGES[Math.floor(Math.random() * FUNNY_MESSAGES.length)]!;
+}
+
+function startCycling() {
+  funnyMessage.value = pickFunnyMessage();
+  messageInterval = setInterval(() => {
+    funnyMessage.value = pickFunnyMessage();
+  }, 3600);
+}
+
+function stopCycling() {
+  if (messageInterval !== null) {
+    clearInterval(messageInterval);
+    messageInterval = null;
+  }
+  funnyMessage.value = null;
+}
+
+watch(
+  () => spinnerState.visible,
+  (visible) => {
+    if (visible) {
+      startCycling();
+    } else {
+      stopCycling();
+    }
+  },
+  { immediate: true },
+);
+
+onUnmounted(stopCycling);
+</script>
+
+<style scoped>
+.global-spinner-overlay {
+  position: fixed;
+  inset: 0;
+  z-index: 9999;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  gap: 12px;
+  background: color-mix(in srgb, var(--background) 25%, transparent);
+  backdrop-filter: blur(4px);
+  pointer-events: all;
+}
+
+.global-spinner-icon {
+  color: var(--foreground);
+  animation: global-spinner-spin 1s linear infinite;
+}
+
+.global-spinner-official-text {
+  font-size: 0.9rem;
+  font-weight: 500;
+  color: var(--foreground);
+  opacity: 0.7;
+  text-align: center;
+  padding: 0 24px;
+  margin: 0;
+}
+
+.global-spinner-funny-text {
+  font-size: 2rem;
+  font-weight: 700;
+  color: var(--foreground);
+  text-align: center;
+  padding: 0 24px;
+  margin: 0;
+}
+
+@keyframes global-spinner-spin {
+  from {
+    transform: rotate(0deg);
+  }
+  to {
+    transform: rotate(360deg);
+  }
+}
+</style>
diff --git a/src/viewer/viewer_commands.ts b/src/viewer/viewer_commands.ts
index 6903169..d8cabff 100644
--- a/src/viewer/viewer_commands.ts
+++ b/src/viewer/viewer_commands.ts
@@ -365,6 +365,12 @@ export type HandleGeometryCommand =
   | SetGeometryVisibilityCommand
   | ToggleGeometryVisibilityCommand;
 
+export interface SpinnerCommand extends CommandRecord {
+  dispatch: "spinner";
+  visible: boolean;
+  message?: string | null;
+}
+
 export type ViewerCommand =
   | MaterialCommand
   | LightCommand
@@ -375,7 +381,8 @@ export type ViewerCommand =
   | TextTagCommand
   | ObjectInfosCommand
   | ObjectActionCommand
-  | HandleGeometryCommand;
+  | HandleGeometryCommand
+  | SpinnerCommand;
 
 const SCENE_TYPES = new Set<SceneCommandType>([
   "background_color",
@@ -462,6 +469,9 @@ export function parseViewerCommand(record: CommandRecord): ViewerCommand {
     case "handle_geometry":
       validateHandleGeometry(record);
       return record as HandleGeometryCommand;
+    case "spinner":
+      validateSpinner(record);
+      return record as SpinnerCommand;
     default:
       throw new CompasViewerError(
         "unsupported_message",
@@ -750,6 +760,13 @@ function validateHandleGeometry(record: CommandRecord): void {
   if (type === "set_visibility") readBoolean(record, "visible");
 }
 
+function validateSpinner(record: CommandRecord): void {
+  readBoolean(record, "visible");
+  if (record.message !== undefined && record.message !== null) {
+    readOptionalString(record, "message");
+  }
+}
+
 function readNumberFields(record: CommandRecord, fields: string[]): void {
   for (const field of fields) readFiniteNumber(record, field);
 }
diff --git a/src/viewer/viewer_runtime.ts b/src/viewer/viewer_runtime.ts
index c7bc5ef..85c7a5c 100644
--- a/src/viewer/viewer_runtime.ts
+++ b/src/viewer/viewer_runtime.ts
@@ -20,6 +20,7 @@ import {
   type ObjectActionCommand,
   type ObjectInfosCommand,
   type SceneCommand,
+  type SpinnerCommand,
   type TextCommand,
   type TextTagCommand,
   type UiCommand,
@@ -487,6 +488,9 @@ export class ViewerRuntime {
       case "handle_geometry":
         this.handleGeometry(data);
         break;
+      case "spinner":
+        this.manageSpinner(data);
+        break;
     }
   }
 
@@ -679,6 +683,13 @@ export class ViewerRuntime {
     });
   }
 
+  private manageSpinner(data: SpinnerCommand): void {
+    this.store.spinnerState.visible = data.visible;
+    this.store.spinnerState.message = data.visible
+      ? (data.message ?? null)
+      : null;
+  }
+
   private pickFromPointer(event: MouseEvent): void {
     this.renderer.domElement.focus({ preventScroll: true });
     if (
diff --git a/src/viewer/viewer_store.ts b/src/viewer/viewer_store.ts
index bd1384d..1c5f61e 100644
--- a/src/viewer/viewer_store.ts
+++ b/src/viewer/viewer_store.ts
@@ -85,6 +85,7 @@ export interface ViewerStore {
   blockPicker: { value: boolean };
   showEdges: { value: boolean };
   theme: { value: "light" | "dark" };
+  spinnerState: { visible: boolean; message: string | null };
   selectedObjectGuid: { value: string | null };
 }
 
@@ -107,6 +108,11 @@ export function createViewerStore(): ViewerStore {
     blockPicker: reactive({ value: false }),
     showEdges: reactive({ value: false }),
     theme: reactive({ value: "light" as const }),
+    spinnerState: reactive({
+      visible: false,
+      message: null as string | null,
+    }),
+
     selectedObjectGuid: reactive({ value: null as string | null }),
   };
 }
diff --git a/tests/viewer_commands.test.ts b/tests/viewer_commands.test.ts
index f938c35..7d40bd0 100644
--- a/tests/viewer_commands.test.ts
+++ b/tests/viewer_commands.test.ts
@@ -41,7 +41,7 @@ describe("viewer command validation", () => {
 
   it("distinguishes unsupported dispatch and variant values", () => {
     for (const input of [
-      { dispatch: "spinner", type: "show" },
+      { dispatch: "not_a_real_dispatch", type: "show" },
       { dispatch: "scene", type: "unknown_scene_action" },
     ]) {
       expect(() => parseViewerCommand(input)).toThrowError(