diff --git a/packages/polling-example/src/components/WakuPolling.tsx b/packages/polling-example/src/components/WakuPolling.tsx
index 3f69be5..ccaf61f 100644
--- a/packages/polling-example/src/components/WakuPolling.tsx
+++ b/packages/polling-example/src/components/WakuPolling.tsx
@@ -43,7 +43,7 @@ export function WakuPolling({ appName, signer, theme }: WakuPollingProps) {
         <CreateButton
           theme={theme}
           onClick={() => {
-            if ((window as any).ethereum) {
+            if ((window as any)?.ethereum) {
               activateBrowserWallet()
             } else setSelectConnect(true)
           }}
diff --git a/packages/proposal-example/src/components/Proposal.tsx b/packages/proposal-example/src/components/Proposal.tsx
index 3385f86..38313e5 100644
--- a/packages/proposal-example/src/components/Proposal.tsx
+++ b/packages/proposal-example/src/components/Proposal.tsx
@@ -31,7 +31,7 @@ function ProposalListHeader({ votesLength, theme, wakuVoting, tokenBalance, acco
   }, [mobileVersion])
 
   const onConnectClick = useCallback(() => {
-    if ((window as any).ethereum) {
+    if ((window as any)?.ethereum) {
       activateBrowserWallet()
     } else setShowConnectionModal(true)
   }, [])
diff --git a/packages/proposal-hooks/src/hooks/useWakuProposal.ts b/packages/proposal-hooks/src/hooks/useWakuProposal.ts
index 1077083..59346cd 100644
--- a/packages/proposal-hooks/src/hooks/useWakuProposal.ts
+++ b/packages/proposal-hooks/src/hooks/useWakuProposal.ts
@@ -18,8 +18,8 @@ export function useWakuProposal(
       const network = await provider?.getNetwork()
       setChainId(network?.chainId ?? 0)
     }
-    ;(window as any).ethereum.on('chainChanged', updateChainId)
-    return () => (window as any).ethereum.removeListener('chainChanged', updateChainId)
+    ;(window as any)?.ethereum?.on('chainChanged', updateChainId)
+    return () => (window as any)?.ethereum?.removeListener('chainChanged', updateChainId)
   }, [])
 
   useEffect(() => {
diff --git a/packages/react-components/src/components/TopBar.tsx b/packages/react-components/src/components/TopBar.tsx
index 4a8f6c5..f998b39 100644
--- a/packages/react-components/src/components/TopBar.tsx
+++ b/packages/react-components/src/components/TopBar.tsx
@@ -48,7 +48,7 @@ export function TopBar({ logo, title, theme, activate, deactivate, account }: To
           <ConnectButton
             theme={theme}
             onClick={() => {
-              if ((window as any).ethereum) {
+              if ((window as any)?.ethereum) {
                 activate()
               } else setSelectConnect(true)
             }}