diff --git a/webextensions/background/background-cache.js b/webextensions/background/background-cache.js
index 947f5f3c7..df0cdd9b4 100644
--- a/webextensions/background/background-cache.js
+++ b/webextensions/background/background-cache.js
@@ -375,7 +375,7 @@ export async function reserveToCacheTree(windowId) {
     return;
 
   const win = TabsStore.windows.get(windowId);
-  if (!window)
+  if (!win)
     return;
 
   // If there is any opening (but not resolved its unique id yet) tab,
diff --git a/webextensions/background/commands.js b/webextensions/background/commands.js
index 8fb38462e..50aed0aa4 100644
--- a/webextensions/background/commands.js
+++ b/webextensions/background/commands.js
@@ -550,11 +550,11 @@ export async function moveTabsWithStructure(tabs, params = {}) {
   }
 
   if (params.import) {
-    const window = TabsStore.windows.get(destinationWindowId);
+    const win = TabsStore.windows.get(destinationWindowId);
     const initialIndex = params.insertBefore ? params.insertBefore.index :
       params.insertAfter ? params.insertAfter.index+1 :
-        window.tabs.size;
-    window.toBeOpenedOrphanTabs += tabs.length;
+        win.tabs.size;
+    win.toBeOpenedOrphanTabs += tabs.length;
     movedTabs = [];
     let index = 0;
     for (const tab of tabs) {
@@ -919,8 +919,8 @@ export async function openTabInWindow(tab, options = {}) {
       tabId:     tab.id,
       ...getWindowParamsFromSource(sourceWindow, options),
     };
-    const window = await browser.windows.create(windowParams).catch(ApiTabs.createErrorHandler());
-    return window.id;
+    const win = await browser.windows.create(windowParams).catch(ApiTabs.createErrorHandler());
+    return win.id;
   }
 }
 
@@ -1286,9 +1286,9 @@ Sync.onMessage.addListener(async message => {
   });
 
   const windowId = TabsStore.getCurrentWindowId() || (await browser.windows.getCurrent()).id;
-  const window = TabsStore.windows.get(windowId);
-  const initialIndex = window.tabs.size;
-  window.toBeOpenedOrphanTabs += data.tabs.length;
+  const win = TabsStore.windows.get(windowId);
+  const initialIndex = win.tabs.size;
+  win.toBeOpenedOrphanTabs += data.tabs.length;
   let index = 0;
   const tabs = [];
   for (const tab of data.tabs) {
diff --git a/webextensions/common/tabs-store.js b/webextensions/common/tabs-store.js
index 169654854..d1016aaf8 100644
--- a/webextensions/common/tabs-store.js
+++ b/webextensions/common/tabs-store.js
@@ -78,10 +78,10 @@ export function queryAll(query) {
   const startAt = Date.now();
   if (query.windowId || query.ordered) {
     let tabs = [];
-    for (const window of windows.values()) {
-      if (query.windowId && !matched(window.id, query.windowId))
+    for (const win of windows.values()) {
+      if (query.windowId && !matched(win.id, query.windowId))
         continue;
-      const [sourceTabs, offset] = sourceTabsForQuery(query, window);
+      const [sourceTabs, offset] = sourceTabsForQuery(query, win);
       tabs = tabs.concat(query.iterator ? getMatchedTabsIterator(sourceTabs, query, offset) : extractMatchedTabs(sourceTabs, query, offset));
     }
     query.elapsed = Date.now() - startAt;
@@ -106,30 +106,30 @@ export function queryAll(query) {
   }
 }
 
-function sourceTabsForQuery(query, window) {
+function sourceTabsForQuery(query, win) {
   let offset = 0;
   if (!query.ordered)
-    return [query.tabs && query.tabs.values() || window.tabs.values(), offset];
+    return [query.tabs && query.tabs.values() || win.tabs.values(), offset];
   let fromId;
   let toId = query.toId;
   if (typeof query.index == 'number') {
-    fromId = window.order[query.index];
+    fromId = win.order[query.index];
     offset = query.index;
   }
   if (typeof query.fromIndex == 'number') {
-    fromId = window.order[query.fromIndex];
+    fromId = win.order[query.fromIndex];
     offset = query.fromIndex;
   }
   if (typeof query.toIndex == 'number') {
-    toId = window.order[query.toIndex];
+    toId = win.order[query.toIndex];
   }
   if (typeof fromId != 'number') {
     fromId = query.fromId;
-    offset = window.order.indexOf(query.fromId);
+    offset = win.order.indexOf(query.fromId);
   }
   if (query.last || query.reversed)
-    return [window.getReversedOrderedTabs(fromId, toId, query.tabs), offset];
-  return [window.getOrderedTabs(fromId, toId, query.tabs), offset];
+    return [win.getReversedOrderedTabs(fromId, toId, query.tabs), offset];
+  return [win.getOrderedTabs(fromId, toId, query.tabs), offset];
 }
 
 function extractMatchedTabs(tabs, query, offset) {
@@ -283,10 +283,10 @@ export function query(query) {
   const startAt = Date.now();
   let tabs = [];
   if (query.windowId || query.ordered) {
-    for (const window of windows.values()) {
-      if (query.windowId && !matched(window.id, query.windowId))
+    for (const win of windows.values()) {
+      if (query.windowId && !matched(win.id, query.windowId))
         continue;
-      const [sourceTabs, offset] = sourceTabsForQuery(query, window);
+      const [sourceTabs, offset] = sourceTabsForQuery(query, win);
       tabs = tabs.concat(extractMatchedTabs(sourceTabs, query, offset));
       if (tabs.length > 0)
         break;
diff --git a/webextensions/sidebar/gap-canceller.js b/webextensions/sidebar/gap-canceller.js
index be93cb0e4..5b44fed0e 100644
--- a/webextensions/sidebar/gap-canceller.js
+++ b/webextensions/sidebar/gap-canceller.js
@@ -148,8 +148,8 @@ function updateOffset() {
   }
   mLastWindowDimension = dimension;
   mLastMozInnerScreenY = window.mozInnerScreenY;
-  browser.windows.get(mWindowId).then(window => {
-    mDataset.ownerWindowState = window.state;
+  browser.windows.get(mWindowId).then(win => {
+    mDataset.ownerWindowState = win.state;
   });
 }