diff --git a/scripts/networks.js b/scripts/networks.js
index 24533afbdcd..d4fb99379e0 100644
--- a/scripts/networks.js
+++ b/scripts/networks.js
@@ -17,6 +17,7 @@ async function fetchData() {
         badgeURL
       }
       testnet
+      internal
       opStack
       defaultExplorer {
         url
diff --git a/src/__swaps__/screens/Swap/Swap.tsx b/src/__swaps__/screens/Swap/Swap.tsx
index 4838c221cac..da79e3a04f4 100644
--- a/src/__swaps__/screens/Swap/Swap.tsx
+++ b/src/__swaps__/screens/Swap/Swap.tsx
@@ -24,7 +24,7 @@ import { parseSearchAsset } from '@/__swaps__/utils/assets';
 import { AbsolutePortalRoot } from '@/components/AbsolutePortal';
 import { useDelayedMount } from '@/hooks/useDelayedMount';
 import { userAssetsStore } from '@/state/assets/userAssets';
-import { useSwapsStore } from '@/state/swaps/swapsStore';
+import { swapsStore, useSwapsStore } from '@/state/swaps/swapsStore';
 import { SwapWarning } from './components/SwapWarning';
 import { clearCustomGasSettings } from './hooks/useCustomGas';
 import { SwapProvider, useSwapContext } from './providers/swap-provider';
@@ -109,6 +109,7 @@ const useCleanupOnUnmount = () => {
   useEffect(() => {
     return () => {
       const highestValueEth = userAssetsStore.getState().getHighestValueEth();
+      const preferredNetwork = swapsStore.getState().preferredNetwork;
       const parsedAsset = highestValueEth
         ? parseSearchAsset({
             assetWithPrice: undefined,
@@ -123,7 +124,7 @@ const useCleanupOnUnmount = () => {
         outputAsset: null,
         outputSearchQuery: '',
         quote: null,
-        selectedOutputChainId: parsedAsset?.chainId ?? ChainId.mainnet,
+        selectedOutputChainId: parsedAsset?.chainId ?? preferredNetwork ?? ChainId.mainnet,
       });
 
       userAssetsStore.setState({ filter: 'all', inputSearchQuery: '' });
diff --git a/src/__swaps__/screens/Swap/components/GasButton.tsx b/src/__swaps__/screens/Swap/components/GasButton.tsx
index 643cfc7dab1..02532433b44 100644
--- a/src/__swaps__/screens/Swap/components/GasButton.tsx
+++ b/src/__swaps__/screens/Swap/components/GasButton.tsx
@@ -58,7 +58,8 @@ function EstimatedGasFee() {
 }
 
 function SelectedGas({ isPill }: { isPill?: boolean }) {
-  const chainId = swapsStore(s => s.inputAsset?.chainId || ChainId.mainnet);
+  const preferredNetwork = swapsStore(s => s.preferredNetwork);
+  const chainId = swapsStore(s => s.inputAsset?.chainId || preferredNetwork || ChainId.mainnet);
   const selectedGasSpeed = useSelectedGasSpeed(chainId);
 
   return (
@@ -108,7 +109,8 @@ function keys<const T extends string>(obj: Record<T, unknown> | undefined) {
 const GasMenu = ({ backToReview = false, children }: { backToReview?: boolean; children: ReactNode }) => {
   const { SwapNavigation } = useSwapContext();
 
-  const chainId = swapsStore(s => s.inputAsset?.chainId || ChainId.mainnet);
+  const preferredNetwork = swapsStore(s => s.preferredNetwork);
+  const chainId = swapsStore(s => s.inputAsset?.chainId || preferredNetwork || ChainId.mainnet);
   const metereologySuggestions = useMeteorologySuggestions({ chainId });
   const customGasSettings = useCustomGasSettings(chainId);
 
diff --git a/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts b/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts
index a77dccd683d..9d47932ba9b 100644
--- a/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts
+++ b/src/__swaps__/screens/Swap/hooks/useEstimatedGasFee.ts
@@ -6,10 +6,11 @@ import { useMemo } from 'react';
 import { formatUnits } from 'viem';
 
 import { useAccountSettings } from '@/hooks';
-import { useSyncedSwapQuoteStore } from '../providers/SyncSwapStateAndSharedValues';
+import { calculateGasFeeWorklet, useSyncedSwapQuoteStore } from '../providers/SyncSwapStateAndSharedValues';
 import { GasSettings } from './useCustomGas';
 import { useSelectedGas } from './useSelectedGas';
 import { useSwapEstimatedGasLimit } from './useSwapEstimatedGasLimit';
+import { useSwapsStore } from '@/state/swaps/swapsStore';
 
 function safeBigInt(value: string) {
   try {
@@ -19,24 +20,6 @@ function safeBigInt(value: string) {
   }
 }
 
-const isFeeNaN = (value: string | undefined) => isNaN(Number(value)) || typeof value === 'undefined';
-
-export function calculateGasFee(gasSettings: GasSettings, gasLimit: string) {
-  if (gasSettings.isEIP1559) {
-    if (isFeeNaN(gasSettings.maxBaseFee) || isFeeNaN(gasSettings.maxPriorityFee)) {
-      return null;
-    }
-
-    return add(gasSettings.maxBaseFee, gasSettings.maxPriorityFee);
-  }
-
-  if (isFeeNaN(gasSettings.gasPrice)) {
-    return null;
-  }
-
-  return multiply(gasLimit, gasSettings.gasPrice);
-}
-
 export function useEstimatedGasFee({
   chainId,
   gasLimit,
@@ -52,13 +35,15 @@ export function useEstimatedGasFee({
   return useMemo(() => {
     if (!gasLimit || !gasSettings || !nativeNetworkAsset?.price) return;
 
-    const fee = calculateGasFee(gasSettings, gasLimit);
-    if (!fee) return;
+    const gasFee = calculateGasFeeWorklet(gasSettings, gasLimit);
+    if (isNaN(Number(gasFee))) {
+      return;
+    }
 
     const networkAssetPrice = nativeNetworkAsset.price.value?.toString();
-    if (!networkAssetPrice) return `${formatNumber(weiToGwei(fee))} Gwei`;
+    if (!networkAssetPrice) return `${formatNumber(weiToGwei(gasFee))} Gwei`;
 
-    const feeFormatted = formatUnits(safeBigInt(fee), nativeNetworkAsset.decimals).toString();
+    const feeFormatted = formatUnits(safeBigInt(gasFee), nativeNetworkAsset.decimals).toString();
     const feeInUserCurrency = multiply(networkAssetPrice, feeFormatted);
 
     return convertAmountToNativeDisplayWorklet(feeInUserCurrency, nativeCurrency, true);
@@ -66,7 +51,8 @@ export function useEstimatedGasFee({
 }
 
 export function useSwapEstimatedGasFee(overrideGasSettings?: GasSettings) {
-  const { assetToSell, quote, chainId = ChainId.mainnet } = useSyncedSwapQuoteStore();
+  const preferredNetwork = useSwapsStore(s => s.preferredNetwork);
+  const { assetToSell, quote, chainId = preferredNetwork || ChainId.mainnet } = useSyncedSwapQuoteStore();
   const gasSettings = useSelectedGas(chainId);
 
   const { data: estimatedGasLimit, isFetching } = useSwapEstimatedGasLimit({ chainId, assetToSell, quote });
diff --git a/src/__swaps__/screens/Swap/hooks/useNativeAssetForChain.ts b/src/__swaps__/screens/Swap/hooks/useNativeAssetForChain.ts
index 3e3792d88b8..ffd07d2654c 100644
--- a/src/__swaps__/screens/Swap/hooks/useNativeAssetForChain.ts
+++ b/src/__swaps__/screens/Swap/hooks/useNativeAssetForChain.ts
@@ -6,9 +6,10 @@ import { ChainId } from '@/chains/types';
 import { SharedValue, runOnJS, useAnimatedReaction, useDerivedValue, useSharedValue } from 'react-native-reanimated';
 import { ParsedAddressAsset } from '@/entities';
 import { ethereumUtils } from '@/utils';
+import { swapsStore } from '@/state/swaps/swapsStore';
 
 export const useNativeAssetForChain = ({ inputAsset }: { inputAsset: SharedValue<ExtendedAnimatedAssetWithColors | null> }) => {
-  const chainId = useDerivedValue(() => inputAsset.value?.chainId ?? ChainId.mainnet);
+  const chainId = useDerivedValue(() => inputAsset.value?.chainId ?? swapsStore.getState().preferredNetwork ?? ChainId.mainnet);
   const nativeAsset = useSharedValue<ParsedAddressAsset | undefined>(ethereumUtils.getNetworkNativeAsset({ chainId: chainId.value }));
 
   const getNativeAssetForNetwork = useCallback(
diff --git a/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx b/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx
index 46dba532c92..99e1dfc56b8 100644
--- a/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx
+++ b/src/__swaps__/screens/Swap/providers/SyncSwapStateAndSharedValues.tsx
@@ -26,6 +26,7 @@ import { GasSettings } from '../hooks/useCustomGas';
 import { useSelectedGas } from '../hooks/useSelectedGas';
 import { useSwapEstimatedGasLimit } from '../hooks/useSwapEstimatedGasLimit';
 import { useSwapContext } from './swap-provider';
+import { useSwapsStore } from '@/state/swaps/swapsStore';
 
 const BUFFER_RATIO = 0.5;
 
@@ -89,18 +90,13 @@ export function calculateGasFeeWorklet(gasSettings: GasSettings, gasLimit: strin
   'worklet';
 
   if (gasSettings.isEIP1559) {
-    if (isFeeNaNWorklet(gasSettings.maxBaseFee) || isFeeNaNWorklet(gasSettings.maxPriorityFee)) {
-      return null;
-    }
-
-    return sumWorklet(gasSettings.maxBaseFee || '0', gasSettings.maxPriorityFee || '0');
-  }
-
-  if (isFeeNaNWorklet(gasSettings.gasPrice)) {
-    return null;
+    const maxBaseFee = isFeeNaNWorklet(gasSettings.maxBaseFee) ? '0' : gasSettings.maxBaseFee;
+    const maxPriorityFee = isFeeNaNWorklet(gasSettings.maxPriorityFee) ? '0' : gasSettings.maxPriorityFee;
+    return mulWorklet(gasLimit, sumWorklet(maxBaseFee, maxPriorityFee));
   }
 
-  return mulWorklet(gasLimit, gasSettings.gasPrice);
+  const gasPrice = isFeeNaNWorklet(gasSettings.gasPrice) ? '0' : gasSettings.gasPrice;
+  return mulWorklet(gasLimit, gasPrice);
 }
 
 export function formatUnitsWorklet(value: string, decimals: number) {
@@ -138,8 +134,12 @@ const getHasEnoughFundsForGasWorklet = ({
 
 export function SyncGasStateToSharedValues() {
   const { hasEnoughFundsForGas, internalSelectedInputAsset } = useSwapContext();
+  const preferredNetwork = useSwapsStore(s => s.preferredNetwork);
 
-  const initialChainId = useMemo(() => internalSelectedInputAsset.value?.chainId || ChainId.mainnet, [internalSelectedInputAsset]);
+  const initialChainId = useMemo(
+    () => internalSelectedInputAsset.value?.chainId || preferredNetwork || ChainId.mainnet,
+    [internalSelectedInputAsset, preferredNetwork]
+  );
   const { assetToSell, chainId = initialChainId, quote } = useSyncedSwapQuoteStore();
 
   const gasSettings = useSelectedGas(chainId);
@@ -198,7 +198,7 @@ export function SyncGasStateToSharedValues() {
       }
 
       const gasFee = calculateGasFeeWorklet(gasSettings, estimatedGasLimit);
-      if (gasFee === null || isNaN(Number(gasFee))) {
+      if (isNaN(Number(gasFee))) {
         return;
       }
 
diff --git a/src/chains/types.ts b/src/chains/types.ts
index 9592c5c199f..92425c2c14a 100644
--- a/src/chains/types.ts
+++ b/src/chains/types.ts
@@ -147,6 +147,7 @@ export interface BackendNetwork {
     badgeURL: string;
   };
   testnet: boolean;
+  internal: boolean;
   opStack: boolean;
   defaultExplorer: {
     url: string;
diff --git a/src/chains/utils/backendNetworks.ts b/src/chains/utils/backendNetworks.ts
index 61715e2650b..0082b40abd0 100644
--- a/src/chains/utils/backendNetworks.ts
+++ b/src/chains/utils/backendNetworks.ts
@@ -1,7 +1,7 @@
 import { Chain } from 'viem';
 import { mainnet } from 'viem/chains';
 
-import { RPC_PROXY_API_KEY } from '@/env';
+import { IS_DEV, RPC_PROXY_API_KEY } from '@/env';
 import { BackendNetwork } from '../types';
 
 const proxyBackendNetworkRpcEndpoint = (endpoint: string) => {
@@ -45,5 +45,5 @@ export function transformBackendNetworksToChains(networks?: BackendNetwork[]): C
   if (!networks) {
     return [];
   }
-  return networks.map(network => transformBackendNetworkToChain(network));
+  return networks.filter(network => IS_DEV || !network.internal).map(network => transformBackendNetworkToChain(network));
 }
diff --git a/src/components/DappBrowser/BrowserTab.tsx b/src/components/DappBrowser/BrowserTab.tsx
index 893b0c7f86b..c20d3d5cc17 100644
--- a/src/components/DappBrowser/BrowserTab.tsx
+++ b/src/components/DappBrowser/BrowserTab.tsx
@@ -48,7 +48,7 @@ import {
   USER_AGENT,
   USER_AGENT_APPLICATION_NAME,
 } from './constants';
-import { handleProviderRequestApp } from './handleProviderRequest';
+import { getDappHost, handleProviderRequestApp } from './handleProviderRequest';
 import { useAnimatedTab } from './hooks/useAnimatedTab';
 import { useTabScreenshotProvider } from './hooks/useTabScreenshotProvider';
 import { freezeWebsite, getWebsiteMetadata, unfreezeWebsite } from './scripts';
@@ -254,15 +254,15 @@ const FreezableWebViewComponent = ({
     [addRecent, animatedActiveTabIndex, backgroundColor, currentlyOpenTabIds, setLogo, setTitle, tabId, tabUrl]
   );
 
-  const handleOnLoadStart = useCallback(
-    (event: { nativeEvent: { url: string | URL; title: string } }) => {
+  const handleOnLoad = useCallback(
+    (event: WebViewEvent) => {
+      if (event.nativeEvent.loading) return;
       const { origin } = new URL(event.nativeEvent.url);
 
       if (typeof webViewRef !== 'function' && webViewRef?.current) {
         if (!webViewRef?.current) {
           return;
         }
-
         const messenger = appMessenger(webViewRef.current, tabId, origin);
         currentMessengerRef.current = messenger;
       }
@@ -270,19 +270,6 @@ const FreezableWebViewComponent = ({
     [webViewRef, tabId]
   );
 
-  const handleOnLoad = useCallback((event: WebViewEvent) => {
-    if (event.nativeEvent.loading) return;
-    // placeholder
-  }, []);
-
-  const handleOnLoadEnd = useCallback(() => {
-    return;
-  }, []);
-
-  const handleOnError = useCallback(() => {
-    return;
-  }, []);
-
   const handleShouldStartLoadWithRequest = useCallback(
     (request: { url: string }) => {
       if (request.url.startsWith('rainbow://wc') || request.url.startsWith('https://rnbwappdotcom.app.link/')) {
@@ -310,13 +297,13 @@ const FreezableWebViewComponent = ({
 
   const handleNavigationStateChange = useCallback(
     (navState: WebViewNavigation) => {
-      if (navState.url) {
-        runOnUI(updateTabUrlWorklet)(navState.url, tabId);
+      if (navState.navigationType !== 'other' || getDappHost(navState.url) === getDappHost(tabUrl)) {
         // ⚠️ TODO: Reintegrate canGoBack/canGoForward - we can just set it here now, reliably, because this
         // function no longer modifies the same URL state that's passed to the WebView's source prop.
+        runOnUI(updateTabUrlWorklet)(navState.url, tabId);
       }
     },
-    [tabId, updateTabUrlWorklet]
+    [tabUrl, updateTabUrlWorklet, tabId]
   );
 
   const handleOnOpenWindow = useCallback(
@@ -364,10 +351,7 @@ const FreezableWebViewComponent = ({
     <Freeze freeze={!isActiveTab}>
       <TabWebView
         onContentProcessDidTerminate={handleOnContentProcessDidTerminate}
-        onError={handleOnError}
         onLoad={handleOnLoad}
-        onLoadStart={handleOnLoadStart}
-        onLoadEnd={handleOnLoadEnd}
         onLoadProgress={handleOnLoadProgress}
         onMessage={handleOnMessage}
         onNavigationStateChange={handleNavigationStateChange}
diff --git a/src/components/DappBrowser/handleProviderRequest.ts b/src/components/DappBrowser/handleProviderRequest.ts
index 79b64e05abf..c8466c853a4 100644
--- a/src/components/DappBrowser/handleProviderRequest.ts
+++ b/src/components/DappBrowser/handleProviderRequest.ts
@@ -2,8 +2,6 @@ import { Messenger } from '@/browserMessaging/AppMessenger';
 import { AddEthereumChainProposedChain, RequestArguments, RequestResponse, handleProviderRequest } from '@rainbow-me/provider';
 import * as lang from '@/languages';
 
-import { Provider } from '@ethersproject/providers';
-
 import { getProvider } from '@/handlers/web3';
 import { UserRejectedRequestError } from 'viem';
 import { logger } from '@/logger';
diff --git a/src/model/wallet.ts b/src/model/wallet.ts
index 64f7b31232e..3c3b61200ce 100644
--- a/src/model/wallet.ts
+++ b/src/model/wallet.ts
@@ -1006,13 +1006,22 @@ export const getPrivateKey = async (
           lang.t('wallet.authenticate.alert.current_authentication_not_secure_enough')
         );
         return kc.ErrorType.NotAuthenticated;
-      case kc.ErrorType.Unavailable:
+      case kc.ErrorType.Unavailable: {
+        // Retry with checksummed address if needed
+        // (This is to mimic the behavior of other wallets like CB)
+        const checksumAddress = toChecksumAddress(address);
+        if (address !== checksumAddress) {
+          return getPrivateKey(checksumAddress);
+        }
         // This means we couldn't find any matches for this key.
         logger.error(new RainbowError('KC unavailable for PKEY lookup'), { error });
         break;
+      }
       default:
         // This is an unknown error
-        logger.error(new RainbowError('KC unknown error for PKEY lookup'), { error });
+        if (error) {
+          logger.error(new RainbowError('KC unknown error for PKEY lookup'), { error });
+        }
         break;
     }
     return pkey || null;
diff --git a/src/utils/ethereumUtils.ts b/src/utils/ethereumUtils.ts
index fa18c85fd9e..45272e37d94 100644
--- a/src/utils/ethereumUtils.ts
+++ b/src/utils/ethereumUtils.ts
@@ -278,7 +278,7 @@ const getDataString = (func: string, arrVals: string[]) => {
  */
 function getEtherscanHostForNetwork({ chainId }: { chainId: ChainId }): string {
   const base_host = 'etherscan.io';
-  const blockExplorer = defaultChains[chainId].blockExplorers?.default?.url;
+  const blockExplorer = defaultChains[chainId]?.blockExplorers?.default?.url;
   const network = chainsName[chainId];
 
   if (network && isTestnetChain({ chainId })) {
@@ -354,7 +354,7 @@ export const getFirstTransactionTimestamp = async (address: EthereumAddress): Pr
 };
 
 function getBlockExplorer({ chainId }: { chainId: ChainId }) {
-  return defaultChains[chainId].blockExplorers?.default.name || 'etherscan';
+  return defaultChains[chainId]?.blockExplorers?.default.name || 'etherscan';
 }
 
 function openAddressInBlockExplorer({ address, chainId }: { address: EthereumAddress; chainId: ChainId }) {