diff --git a/dashboard/src/components/DockerRegistryDialog.vue b/dashboard/src/components/DockerRegistryDialog.vue
index 2e647bdec..2399d7907 100644
--- a/dashboard/src/components/DockerRegistryDialog.vue
+++ b/dashboard/src/components/DockerRegistryDialog.vue
@@ -66,6 +66,7 @@ async function onSubmit() {
 
 defineExpose({
   async open(r = null) {
+    r = r ? JSON.parse(JSON.stringify(r)) : null; // make a copy
     busy.value = false;
     formError.value = {};
     registry.value = r;
diff --git a/dashboard/src/components/DomainDialog.vue b/dashboard/src/components/DomainDialog.vue
index a49482200..5c4d00c62 100644
--- a/dashboard/src/components/DomainDialog.vue
+++ b/dashboard/src/components/DomainDialog.vue
@@ -63,7 +63,7 @@ async function onSubmit() {
 
 defineExpose({
   open(d) {
-    d = d || { config: {}, tlsConfig: {}};
+    d = d ? JSON.parse(JSON.stringify(d)) : { config: {}, tlsConfig: {} }; // make a copy
 
     provider.value = d.provider || '';
     dnsConfig.value = d.config;
diff --git a/dashboard/src/components/GroupDialog.vue b/dashboard/src/components/GroupDialog.vue
index b14df8ee3..c12f6db0a 100644
--- a/dashboard/src/components/GroupDialog.vue
+++ b/dashboard/src/components/GroupDialog.vue
@@ -53,6 +53,7 @@ async function onSubmit() {
 
 defineExpose({
   async open(g = null) {
+    g = g ? JSON.parse(JSON.stringify(g)) : null; // make a copy
     group.value = g;
     name.value = g ? g.name : '';
     formError.value = {};
diff --git a/dashboard/src/components/ImpersonateDialog.vue b/dashboard/src/components/ImpersonateDialog.vue
index c61a0b8a9..8492453d4 100644
--- a/dashboard/src/components/ImpersonateDialog.vue
+++ b/dashboard/src/components/ImpersonateDialog.vue
@@ -42,6 +42,7 @@ async function onSubmit() {
 
 defineExpose({
   async open(u) {
+    u = JSON.parse(JSON.stringify(u)); // make a copy
     user.value = u;
     success.value = false;
     password.value = '';
diff --git a/dashboard/src/components/InvitationDialog.vue b/dashboard/src/components/InvitationDialog.vue
index 274ce2ece..33e40c569 100644
--- a/dashboard/src/components/InvitationDialog.vue
+++ b/dashboard/src/components/InvitationDialog.vue
@@ -31,6 +31,7 @@ async function onSendInvite() {
 
 defineExpose({
   async open(u) {
+    u = JSON.parse(JSON.stringify(u)); // make a copy
     user.value = u;
     success.value = false;
     email.value = u.email || '';
diff --git a/dashboard/src/components/MailboxDialog.vue b/dashboard/src/components/MailboxDialog.vue
index f915b5254..e043b54c9 100644
--- a/dashboard/src/components/MailboxDialog.vue
+++ b/dashboard/src/components/MailboxDialog.vue
@@ -85,6 +85,7 @@ async function onSubmit() {
 
 defineExpose({
   async open(m = null) {
+    m = m ? JSON.parse(JSON.stringify(m)) : null; // make a copy
     busy.value = false;
     formError.value = '';
     mailbox.value = m;
@@ -92,7 +93,7 @@ defineExpose({
     name.value = m ? m.name : '';
     domain.value = m ? m.domain : props.domains[0].domain;
     ownerId.value = m ? m.ownerId : '';
-    aliases.value = m ? JSON.parse(JSON.stringify(m.aliases)) : [];
+    aliases.value = m ? m.aliases : [];
     active.value = m ? m.active : true;
     enablePop3.value = m ? m.enablePop3 : false;
     storageQuotaEnabled.value = m && m.storageQuota ? true : false;
diff --git a/dashboard/src/components/MailinglistDialog.vue b/dashboard/src/components/MailinglistDialog.vue
index 6875d810f..8153de064 100644
--- a/dashboard/src/components/MailinglistDialog.vue
+++ b/dashboard/src/components/MailinglistDialog.vue
@@ -57,6 +57,7 @@ async function onSubmit() {
 
 defineExpose({
   async open(m = null) {
+    m = m ? JSON.parse(JSON.stringify(m)) : null; // make a copy
     busy.value = false;
     formError.value = {};
     mailinglist.value = m;
diff --git a/dashboard/src/components/PasswordResetDialog.vue b/dashboard/src/components/PasswordResetDialog.vue
index 6c56ef918..3eb3a3ffa 100644
--- a/dashboard/src/components/PasswordResetDialog.vue
+++ b/dashboard/src/components/PasswordResetDialog.vue
@@ -35,6 +35,7 @@ async function onSend() {
 
 defineExpose({
   async open(u) {
+    u = JSON.parse(JSON.stringify(u)); // make a copy
     user.value = u;
     formError.value = '';
     email.value = u.fallbackEmail || u.email;
diff --git a/dashboard/src/components/UserDialog.vue b/dashboard/src/components/UserDialog.vue
index f1cd9a696..846651d36 100644
--- a/dashboard/src/components/UserDialog.vue
+++ b/dashboard/src/components/UserDialog.vue
@@ -179,6 +179,7 @@ async function onSubmit() {
 
 defineExpose({
   async open(u = null) {
+    u = u ? JSON.parse(JSON.stringify(u)) : null; // make a copy
     busy.value = false;
     formError.value = {};
     user.value = u;
diff --git a/dashboard/src/views/DomainsView.vue b/dashboard/src/views/DomainsView.vue
index 572d30470..c624b6b46 100644
--- a/dashboard/src/views/DomainsView.vue
+++ b/dashboard/src/views/DomainsView.vue
@@ -34,7 +34,7 @@ function onAdd () {
 }
 
 function onEdit(domain) {
-  domainDialog.value.open(domain);
+  domainDialog.value.open(domain); // pass a copy to prevent the dialog from mutating
 }
 
 const inputDialog = useTemplateRef('inputDialog');