diff --git a/src/js/popup.js b/src/js/popup.js
index a9e3d26..2964f02 100644
--- a/src/js/popup.js
+++ b/src/js/popup.js
@@ -212,6 +212,27 @@ const Logic = {
     return false;
   },
 
+  async numTabs() {
+    const activeTabs = await browser.tabs.query({windowId: browser.windows.WINDOW_ID_CURRENT});
+    return activeTabs.length;
+  },
+
+  _disableMoveTabs(message) {
+    const moveTabsEl = document.querySelector("#container-info-movetabs");
+    const fragment = document.createDocumentFragment();
+    const incompatEl = document.createElement("div");
+
+    moveTabsEl.classList.remove("clickable");
+    moveTabsEl.setAttribute("title", message);
+
+    fragment.appendChild(incompatEl);
+    incompatEl.setAttribute("id", "container-info-movetabs-incompat");
+    incompatEl.textContent = message;
+    incompatEl.classList.add("container-info-tab-row");
+
+    moveTabsEl.parentNode.insertBefore(fragment, moveTabsEl.nextSibling);
+  },
+
   async refreshIdentities() {
     const [identities, state] = await Promise.all([
       browser.contextualIdentities.query({}),
@@ -698,37 +719,31 @@ Logic.registerPanel(P_CONTAINER_INFO, {
     });
 
     // Check if the user has incompatible add-ons installed
+    let incompatible = false;
     try {
-      const incompatible = await browser.runtime.sendMessage({
+      incompatible = await browser.runtime.sendMessage({
         method: "checkIncompatibleAddons"
       });
-      const moveTabsEl = document.querySelector("#container-info-movetabs");
-      if (incompatible) {
-        const fragment = document.createDocumentFragment();
-        const incompatEl = document.createElement("div");
-
-        moveTabsEl.classList.remove("clickable");
-        moveTabsEl.setAttribute("title", "Moving container tabs is incompatible with Pulse, PageShot, and SnoozeTabs.");
-
-        fragment.appendChild(incompatEl);
-        incompatEl.setAttribute("id", "container-info-movetabs-incompat");
-        incompatEl.textContent = "Incompatible with other Experiments.";
-        incompatEl.classList.add("container-info-tab-row");
-
-        moveTabsEl.parentNode.insertBefore(fragment, moveTabsEl.nextSibling);
-      } else {
-        Logic.addEnterHandler(moveTabsEl, async function () {
-          await browser.runtime.sendMessage({
-            method: "moveTabsToWindow",
-            windowId: browser.windows.WINDOW_ID_CURRENT,
-            cookieStoreId: Logic.currentIdentity().cookieStoreId,
-          });
-          window.close();
-        });
-      }
     } catch (e) {
       throw new Error("Could not check for incompatible add-ons.");
     }
+    const moveTabsEl = document.querySelector("#container-info-movetabs");
+    const numTabs = await Logic.numTabs();
+    if (incompatible) {
+      Logic._disableMoveTabs("Moving container tabs is incompatible with Pulse, PageShot, and SnoozeTabs.");
+      return;
+    } else if (numTabs === 1) {
+      Logic._disableMoveTabs("Cannot move a tab from a single-tab window.");
+      return; 
+    }
+    Logic.addEnterHandler(moveTabsEl, async function () {
+      await browser.runtime.sendMessage({
+        method: "moveTabsToWindow",
+        windowId: browser.windows.WINDOW_ID_CURRENT,
+        cookieStoreId: Logic.currentIdentity().cookieStoreId,
+      });
+      window.close();
+    });
   },
 
   // This method is called when the panel is shown.