From a8b1d02123bc7e5368efc0d37de20489bf5ed7db Mon Sep 17 00:00:00 2001
From: deckertron9000 <10391684+deckertron9000@users.noreply.github.com>
Date: Thu, 2 Apr 2026 09:43:17 -0500
Subject: [PATCH] fix(message): show original sender for Firefox Relay emails

When a display name contains an email address (e.g. Firefox Relay's
"original@sender.com [via Relay]" format), spoof prevention was
suppressing the display name entirely and showing only the relay
address. This aligns with how Thunderbird Desktop handles it by
expanding to show both the display name and the actual address in
"personal <address>" format.

Fixes #7367
---
 .../java/com/fsck/k9/helper/MessageHelper.kt   |  8 ++++----
 .../com/fsck/k9/helper/MessageHelperTest.kt    | 18 ++++++++++++++++--
 .../MessageViewRecipientFormatter.kt           |  6 +++---
 .../MessageViewRecipientFormatterTest.kt       | 16 ++++++++++++++--
 4 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/legacy/core/src/main/java/com/fsck/k9/helper/MessageHelper.kt b/legacy/core/src/main/java/com/fsck/k9/helper/MessageHelper.kt
index ef56c5c0df5..abadd5ea92f 100644
--- a/legacy/core/src/main/java/com/fsck/k9/helper/MessageHelper.kt
+++ b/legacy/core/src/main/java/com/fsck/k9/helper/MessageHelper.kt
@@ -153,10 +153,10 @@ class MessageHelper(
                 }
             }
             val personal = address.personal
-            return if (!personal.isNullOrEmpty() && !isSpoofAddress(personal)) {
-                personal
-            } else {
-                address.address
+            return when {
+                personal.isNullOrEmpty() -> address.address
+                isSpoofAddress(personal) -> "$personal <${address.address}>"
+                else -> personal
             }
         }
 
diff --git a/legacy/core/src/test/java/com/fsck/k9/helper/MessageHelperTest.kt b/legacy/core/src/test/java/com/fsck/k9/helper/MessageHelperTest.kt
index dd0f46e5fc7..b10088bd851 100644
--- a/legacy/core/src/test/java/com/fsck/k9/helper/MessageHelperTest.kt
+++ b/legacy/core/src/test/java/com/fsck/k9/helper/MessageHelperTest.kt
@@ -133,7 +133,7 @@ class MessageHelperTest : RobolectricTest() {
     }
 
     @Test
-    fun toFriendly_spoofPreventionOverridesPersonal() {
+    fun toFriendly_spoofPreventionExpandsToShowBothPersonalAndAddress() {
         val address = Address("test@testor.com", "potus@whitehouse.gov")
         val friendly =
             toFriendly(
@@ -143,7 +143,21 @@ class MessageHelperTest : RobolectricTest() {
                 messageListPreferencesManager.getConfig().contactNameColor,
                 contactRepository,
             )
-        assertThat(friendly).isEqualTo("test@testor.com")
+        assertThat(friendly).isEqualTo("potus@whitehouse.gov <test@testor.com>")
+    }
+
+    @Test
+    fun toFriendly_firefoxRelayAddressShowsOriginalSenderAndRelayAddress() {
+        val address = Address("alias123@mozmail.com", "sender@example.com [via Relay]")
+        val friendly =
+            toFriendly(
+                address,
+                messageListPreferencesManager.getConfig().isShowCorrespondentNames,
+                messageListPreferencesManager.getConfig().isChangeContactNameColor,
+                messageListPreferencesManager.getConfig().contactNameColor,
+                contactRepository,
+            )
+        assertThat(friendly).isEqualTo("sender@example.com [via Relay] <alias123@mozmail.com>")
     }
 
     @Test
diff --git a/legacy/ui/legacy/src/main/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatter.kt b/legacy/ui/legacy/src/main/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatter.kt
index 8181886ad26..a0ee92065ac 100644
--- a/legacy/ui/legacy/src/main/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatter.kt
+++ b/legacy/ui/legacy/src/main/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatter.kt
@@ -61,9 +61,9 @@ internal class RealMessageViewRecipientFormatter(
     }
 
     private fun buildDisplayName(address: Address): CharSequence {
-        return address.personal?.takeIf {
-            it.isNotBlank() && !it.equals(meText, ignoreCase = true) && !isSpoofAddress(it)
-        } ?: address.address
+        val personal = address.personal?.takeIf { it.isNotBlank() && !it.equals(meText, ignoreCase = true) }
+            ?: return address.address
+        return if (isSpoofAddress(personal)) "$personal <${address.address}>" else personal
     }
 
     private fun isSpoofAddress(displayName: String): Boolean {
diff --git a/legacy/ui/legacy/src/test/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatterTest.kt b/legacy/ui/legacy/src/test/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatterTest.kt
index ad2d08b17b7..70b079227c9 100644
--- a/legacy/ui/legacy/src/test/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatterTest.kt
+++ b/legacy/ui/legacy/src/test/java/com/fsck/k9/ui/messageview/MessageViewRecipientFormatterTest.kt
@@ -152,7 +152,7 @@ class MessageViewRecipientFormatterTest : RobolectricTest() {
     }
 
     @Test
-    fun `do not show display name that looks like an email address`() {
+    fun `spoof prevention expands to show both display name and actual address`() {
         val recipientFormatter = createRecipientFormatter()
 
         val displayName = recipientFormatter.getDisplayName(
@@ -160,7 +160,19 @@ class MessageViewRecipientFormatterTest : RobolectricTest() {
             account,
         )
 
-        assertThat(displayName).isEqualTo("mallory@domain.example")
+        assertThat(displayName).isEqualTo("potus@whitehouse.gov <mallory@domain.example>")
+    }
+
+    @Test
+    fun `firefox relay address shows original sender and relay address`() {
+        val recipientFormatter = createRecipientFormatter()
+
+        val displayName = recipientFormatter.getDisplayName(
+            Address("alias123@mozmail.com", "sender@example.com [via Relay]"),
+            account,
+        )
+
+        assertThat(displayName).isEqualTo("sender@example.com [via Relay] <alias123@mozmail.com>")
     }
 
     @Test