Revert "Revert "remove offline message for testnet4 (#76)" (#78)" (#85)

This reverts commit 14316163e4.

src/hooks/useSelectedNetwork.ts

@@ -1,7 +1,6 @@
-import { useCallback, useEffect } from 'react';
+import { useCallback } from 'react';
 import { useDispatch, useSelector } from 'react-redux';
 
-import { DialogTypes } from '@/constants/dialogs';
 import { LocalStorageKey } from '@/constants/localStorage';
 import { DEFAULT_APP_ENVIRONMENT, DydxNetwork, ENVIRONMENT_CONFIG_MAP } from '@/constants/networks';
 
@@ -9,7 +8,6 @@ import { useAccounts, useLocalStorage } from '@/hooks';
 
 import { setSelectedNetwork } from '@/state/app';
 import { getSelectedNetwork } from '@/state/appSelectors';
-import { openDialog } from '@/state/dialogs';
 
 import { validateAgainstAvailableEnvironments } from '@/lib/network';
 
@@ -27,17 +25,6 @@ export const useSelectedNetwork = (): {
     validateFn: validateAgainstAvailableEnvironments,
   });
 
-  useEffect(() => {
-    if (
-      import.meta.env.MODE === 'production' &&
-      ENVIRONMENT_CONFIG_MAP[selectedNetwork].dydxChainId === 'dydx-testnet-4'
-    ) {
-      dispatch(
-        openDialog({ type: DialogTypes.ExchangeOffline, dialogProps: { preventClose: true } })
-      );
-    }
-  }, [selectedNetwork]);
-
   const switchNetwork = useCallback(
     (network: DydxNetwork) => {
       disconnect();