diff --git a/frontend/controller/app/identity.js b/frontend/controller/app/identity.js
index 1b8fdb48c..56408316d 100644
--- a/frontend/controller/app/identity.js
+++ b/frontend/controller/app/identity.js
@@ -425,16 +425,21 @@ export default (sbp('sbp/selectors/register', {
           const errMessage = e?.message || String(e)
           console.error('[gi.app/identity] Error during login contract sync', e)
 
+          const wipeOut = (e && (e.name === 'ChelErrorForkedChain' || e.cause?.name === 'ChelErrorForkedChain'))
+
           const promptOptions = {
             heading: L('Login error'),
-            question: L('Do you want to log out? {br_}Error details: {err}.', { err: errMessage, ...LTags() }),
+            question: wipeOut
+              ? L('The server\'s history for your identity contract has diverged from ours. This can happen in extremely rare circumstances due to either malicious activity or a bug. {br_}To fix this, the contract needs to be resynced, and some recent events may be missing. {br_}Would you like to log out and resync data on your next login? {br_}Error details: {err}.', { err: errMessage, ...LTags() })
+              : L('Do you want to log out? {br_}Error details: {err}.', { err: errMessage, ...LTags() }),
             primaryButton: L('No'),
             secondaryButton: L('Yes')
           }
 
           const result = await sbp('gi.ui/prompt', promptOptions)
           if (!result) {
-            return sbp('gi.app/identity/_private/logout', state)
+            sbp('gi.ui/clearBanner')
+            return sbp('gi.app/identity/_private/logout', state, wipeOut)
           } else {
             sbp('okTurtles.events/emit', LOGIN_ERROR, { username, identityContractID, error: e })
             throw e
diff --git a/frontend/main.js b/frontend/main.js
index 0b09877b2..1712ac8b4 100644
--- a/frontend/main.js
+++ b/frontend/main.js
@@ -109,6 +109,15 @@ async function startApp () {
     sbp('gi.ui/seriousErrorBanner', error)
     if (error?.name === 'ChelErrorForkedChain') {
       const rootState = sbp('state/vuex/state')
+      if (!rootState.contracts[contractID]) {
+        // If `rootState.contracts[contractID]` doesn't exist, it means we're no
+        // longer subscribed to the contract. This could happen, e.g., if the
+        // contract has since been released. In any case, the absence of
+        // `rootState.contracts[contractID]` means that there's nothing to
+        // left to recover.
+        console.error('Forked chain detected. However, there is no contract entry.', { contractID }, error)
+        return
+      }
       const type = rootState.contracts[contractID].type || '(unknown)'
       console.error('Forked chain detected', { contractID, type }, error)
 
@@ -116,10 +125,15 @@ async function startApp () {
 
       if (retry) {
         sbp('gi.ui/clearBanner')
-        sbp('chelonia/contract/sync', contractID, { resync: true }).catch((e) => {
-          console.error('Error during re-sync', contractID, e)
-          alert(L('There was a problem resyncing the contract: {errMsg}\n\nPlease see the Application Logs under User Settings for more details. The Troubleshooting page in User Settings may be another way to fix the problem.', { errMsg: e?.message || e }))
-        })
+        // If it's our identity contract, we need to log in again to be able
+        // to propery decrypt all data, since that requires the user password
+        ;((rootState.loggedIn?.identityContractID === contractID)
+          ? sbp('gi.actions/identity/logout', null, true)
+          : sbp('chelonia/contract/sync', contractID, { resync: true }))
+          .catch((e) => {
+            console.error('Error during re-sync', contractID, e)
+            alert(L('There was a problem resyncing the contract: {errMsg}\n\nPlease see the Application Logs under User Settings for more details. The Troubleshooting page in User Settings may be another way to fix the problem.', { errMsg: e?.message || e }))
+          })
       }
     }
     if (process.env.CI) {
diff --git a/shared/domains/chelonia/errors.js b/shared/domains/chelonia/errors.js
index bf5923fd6..860a43a90 100644
--- a/shared/domains/chelonia/errors.js
+++ b/shared/domains/chelonia/errors.js
@@ -14,7 +14,7 @@ export const ChelErrorGenerator = (
       // $FlowFixMe[prop-missing]
       if (params[1]?.cause !== this.cause) {
         // $FlowFixMe[prop-missing]
-        Object.defineProperty(this, 'cause', { value: params[1].cause })
+        Object.defineProperty(this, 'cause', { configurable: true, writable: true, value: params[1].cause })
       }
       if (Error.captureStackTrace) {
         Error.captureStackTrace(this, this.constructor)
diff --git a/shared/serdes/index.js b/shared/serdes/index.js
index b4c992016..2f1473908 100644
--- a/shared/serdes/index.js
+++ b/shared/serdes/index.js
@@ -68,6 +68,10 @@ export const serializer = (data: any): any => {
     if (value instanceof Error) {
       const pos = verbatim.length
       verbatim[verbatim.length] = value
+      // We need to also serialize `Error.cause` recursively
+      if (value.cause) {
+        value.cause = serializer(value.cause).data
+      }
       return rawResult(['_', '_err', rawResult(['_', '_ref', pos]), value.name])
     }
     // Same for other types supported by structuredClone but not JSON
@@ -177,6 +181,9 @@ export const deserializer = (data: any): any => {
           if (value[2].name !== value[3]) {
             value[2].name = value[3]
           }
+          if (value[2].cause) {
+            value[2].cause = deserializer(value[2].cause)
+          }
           return value[2]
         }
         // These were functions converted to a MessagePort. Convert them on this