use domains for relay data, path is fixed

apps/ios/Shared/Views/Chat/Group/ChannelWebAccessView.swift

@@ -116,16 +116,16 @@ struct ChannelWebAccessView: View {
         return webPage != currentWebPage || allowEmbedding != currentEmbedding
     }
 
-    private var relayUrls: [String] {
-        groupRelays.compactMap { $0.relayCap.baseWebUrl }
+    private var relayDomains: [String] {
+        groupRelays.compactMap { $0.relayCap.webDomain }
     }
 
     private var embedCode: String? {
         if let pg = groupInfo.groupProfile.publicGroup,
-           !relayUrls.isEmpty {
+           !relayDomains.isEmpty {
             """
             <div data-simplex-group-preview
-                 data-relay-urls="\(relayUrls.joined(separator: ","))"
+                 data-relay-domains="\(relayDomains.joined(separator: ","))"
                  data-public-group-id="\(pg.publicGroupId)"
                  data-group-link="\(pg.groupLink)"></div>
             <script src="https://simplex.chat/js/channel-preview.js"></script>

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/views/chat/group/ChannelWebPageView.kt

@@ -172,11 +172,11 @@ private fun ChannelWebPageLayout(
 
 private fun embedCode(groupRelays: List<GroupRelay>, groupInfo: GroupInfo): String? {
   val pg = groupInfo.groupProfile.publicGroup ?: return null
-  val relayUrls = groupRelays.mapNotNull { it.relayCap.baseWebUrl }
-  if (relayUrls.isEmpty()) return null
-  val urls = relayUrls.joinToString(",")
+  val relayDomains = groupRelays.mapNotNull { it.relayCap.webDomain }
+  if (relayDomains.isEmpty()) return null
+  val domains = relayDomains.joinToString(",")
   return """<div data-simplex-group-preview
-     data-relay-urls="$urls"
+     data-relay-domains="$domains"
      data-public-group-id="${pg.publicGroupId}"
      data-group-link="${pg.groupLink}"></div>
 <script src="https://simplex.chat/js/channel-preview.js"></script>"""

simplex-chat.cabal

@@ -138,7 +138,7 @@ library
           Simplex.Chat.Store.Postgres.Migrations.M20260529_delivery_job_senders
           Simplex.Chat.Store.Postgres.Migrations.M20260530_client_services
           Simplex.Chat.Store.Postgres.Migrations.M20260531_member_removed_at
-          Simplex.Chat.Store.Postgres.Migrations.M20260531_relay_sent_web_url
+          Simplex.Chat.Store.Postgres.Migrations.M20260531_relay_sent_web_domain
   else
       exposed-modules:
           Simplex.Chat.Archive
@@ -298,7 +298,7 @@ library
           Simplex.Chat.Store.SQLite.Migrations.M20260529_delivery_job_senders
           Simplex.Chat.Store.SQLite.Migrations.M20260530_client_services
           Simplex.Chat.Store.SQLite.Migrations.M20260531_member_removed_at
-          Simplex.Chat.Store.SQLite.Migrations.M20260531_relay_sent_web_url
+          Simplex.Chat.Store.SQLite.Migrations.M20260531_relay_sent_web_domain
   other-modules:
       Paths_simplex_chat
   hs-source-dirs:

src/Simplex/Chat/Controller.hs

@@ -171,7 +171,7 @@ data ChatConfig = ChatConfig
   }
 
 data WebPreviewConfig = WebPreviewConfig
-  { baseWebUrl :: Text,
+  { webDomain :: Text,
     webJsonDir :: FilePath,
     webCorsFile :: Maybe FilePath,
     webUpdateInterval :: Int -- seconds

src/Simplex/Chat/Library/Commands.hs

@@ -4880,14 +4880,14 @@ runRelayGroupLinkChecks user = do
         sendRelayCapIfNeeded vr gInfo
     sendRelayCapIfNeeded vr gInfo = do
       ChatConfig {webPreviewConfig} <- asks config
-      let currentWebUrl = (\WebPreviewConfig {baseWebUrl} -> baseWebUrl) <$> webPreviewConfig
-      sentWebUrl <- withStore' (`getRelaySentWebUrl` gInfo)
-      when (currentWebUrl /= sentWebUrl) $ do
+      let currentWebDomain = (\WebPreviewConfig {webDomain} -> webDomain) <$> webPreviewConfig
+      sentWebDomain <- withStore' (`getRelaySentWebDomain` gInfo)
+      when (currentWebDomain /= sentWebDomain) $ do
         owners <- withStore' $ \db -> getGroupOwners db vr user gInfo
         let capableOwners = filter (\m -> memberCurrent m && m `supportsVersion` relayWebCapVersion) owners
         unless (null capableOwners) $ do
-          void $ sendGroupMessage' user gInfo capableOwners (XGrpRelayCap RelayCapabilities {baseWebUrl = currentWebUrl})
-          withStore' $ \db -> updateRelaySentWebUrl db gInfo currentWebUrl
+          void $ sendGroupMessage' user gInfo capableOwners (XGrpRelayCap RelayCapabilities {webDomain = currentWebDomain})
+          withStore' $ \db -> updateRelaySentWebDomain db gInfo currentWebDomain
     checkRelayInactiveGroups = do
       vr <- chatVersionRange
       ttl <- asks (relayInactiveTTL . config)

src/Simplex/Chat/Library/Internal.hs

@@ -1046,8 +1046,8 @@ acceptRelayJoinRequestAsync
   cReqChatVRange
   relayLink = do
     ChatConfig {webPreviewConfig} <- asks config
-    let webUrl = (\WebPreviewConfig {baseWebUrl} -> baseWebUrl) <$> webPreviewConfig
-        msg = XGrpRelayAcpt relayLink RelayCapabilities {baseWebUrl = webUrl}
+    let webDomain_ = (\WebPreviewConfig {webDomain} -> webDomain) <$> webPreviewConfig
+        msg = XGrpRelayAcpt relayLink RelayCapabilities {webDomain = webDomain_}
     subMode <- chatReadVar subscriptionMode
     vr <- chatVersionRange
     let chatV = vr `peerConnChatVersion` cReqChatVRange

src/Simplex/Chat/Options.hs

@@ -242,12 +242,12 @@ coreChatOptsP appDir defaultDbName = do
           <> help "Run as a chat relay client"
       )
   webPreviewConfig <- do
-    baseWebUrl_ <-
+    webDomain_ <-
       optional $
         strOption
-          ( long "relay-web-url"
-              <> metavar "URL"
-              <> help "Base URL for channel web previews (relay only)"
+          ( long "relay-web-domain"
+              <> metavar "DOMAIN"
+              <> help "Domain for channel web previews (relay only)"
           )
     webJsonDir_ <-
       optional $
@@ -270,10 +270,10 @@ coreChatOptsP appDir defaultDbName = do
             <> help "Interval between web preview regeneration in seconds (relay only)"
             <> value 300
         )
-    pure $ case (baseWebUrl_, webJsonDir_) of
-      (Just baseWebUrl, Just webJsonDir) -> Just WebPreviewConfig {baseWebUrl, webJsonDir, webCorsFile, webUpdateInterval}
+    pure $ case (webDomain_, webJsonDir_) of
+      (Just webDomain, Just webJsonDir) -> Just WebPreviewConfig {webDomain, webJsonDir, webCorsFile, webUpdateInterval}
       (Nothing, Nothing) -> Nothing
-      _ -> error "--relay-web-url and --relay-web-dir must both be provided"
+      _ -> error "--relay-web-domain and --relay-web-dir must both be provided"
   highlyAvailable <-
     switch
       ( long "ha"

src/Simplex/Chat/Store/Groups.hs

@@ -99,8 +99,8 @@ module Simplex.Chat.Store.Groups
     createRelayRequestGroup,
     updateRelayOwnStatusFromTo,
     updateRelayOwnStatus_,
-    getRelaySentWebUrl,
-    updateRelaySentWebUrl,
+    getRelaySentWebDomain,
+    updateRelaySentWebDomain,
     isRelayGroupRejected,
     allowRelayGroup,
     getRelayServedGroups,
@@ -1644,13 +1644,13 @@ updateRelayOwnStatus_ db GroupInfo {groupId} relayStatus = do
   let inactiveAt_ = if relayStatus == RSInactive then Just currentTs else Nothing
   DB.execute db "UPDATE groups SET relay_own_status = ?, relay_inactive_at = ?, updated_at = ? WHERE group_id = ?" (relayStatus, inactiveAt_, currentTs, groupId)
 
-getRelaySentWebUrl :: DB.Connection -> GroupInfo -> IO (Maybe Text)
-getRelaySentWebUrl db GroupInfo {groupId} =
-  join <$> maybeFirstRow fromOnly (DB.query db "SELECT relay_sent_web_url FROM groups WHERE group_id = ?" (Only groupId))
+getRelaySentWebDomain :: DB.Connection -> GroupInfo -> IO (Maybe Text)
+getRelaySentWebDomain db GroupInfo {groupId} =
+  join <$> maybeFirstRow fromOnly (DB.query db "SELECT relay_sent_web_domain FROM groups WHERE group_id = ?" (Only groupId))
 
-updateRelaySentWebUrl :: DB.Connection -> GroupInfo -> Maybe Text -> IO ()
-updateRelaySentWebUrl db GroupInfo {groupId} webUrl =
-  DB.execute db "UPDATE groups SET relay_sent_web_url = ? WHERE group_id = ?" (webUrl, groupId)
+updateRelaySentWebDomain :: DB.Connection -> GroupInfo -> Maybe Text -> IO ()
+updateRelaySentWebDomain db GroupInfo {groupId} webDomain_ =
+  DB.execute db "UPDATE groups SET relay_sent_web_domain = ? WHERE group_id = ?" (webDomain_, groupId)
 
 -- Flip every RSRejected row sharing the targeted group's relay_request_group_link
 -- to RSInactive in one statement; returns the refreshed GroupInfo for the targeted groupId.

src/Simplex/Chat/Store/Postgres/Migrations.hs

@@ -35,7 +35,7 @@ import Simplex.Chat.Store.Postgres.Migrations.M20260515_public_group_access
 import Simplex.Chat.Store.Postgres.Migrations.M20260529_delivery_job_senders
 import Simplex.Chat.Store.Postgres.Migrations.M20260530_client_services
 import Simplex.Chat.Store.Postgres.Migrations.M20260531_member_removed_at
-import Simplex.Chat.Store.Postgres.Migrations.M20260531_relay_sent_web_url
+import Simplex.Chat.Store.Postgres.Migrations.M20260531_relay_sent_web_domain
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Text, Maybe Text)]
@@ -71,7 +71,7 @@ schemaMigrations =
     ("20260529_delivery_job_senders", m20260529_delivery_job_senders, Just down_m20260529_delivery_job_senders),
     ("20260530_client_services", m20260530_client_services, Just down_m20260530_client_services),
     ("20260531_member_removed_at", m20260531_member_removed_at, Just down_m20260531_member_removed_at),
-    ("20260531_relay_sent_web_url", m20260531_relay_sent_web_url, Just down_m20260531_relay_sent_web_url)
+    ("20260531_relay_sent_web_domain", m20260531_relay_sent_web_domain, Just down_m20260531_relay_sent_web_domain)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/Postgres/Migrations/M20260531_relay_sent_web_domain.hs

@@ -0,0 +1,19 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Store.Postgres.Migrations.M20260531_relay_sent_web_domain where
+
+import Data.Text (Text)
+import Text.RawString.QQ (r)
+
+m20260531_relay_sent_web_domain :: Text
+m20260531_relay_sent_web_domain =
+  [r|
+ALTER TABLE groups ADD COLUMN relay_sent_web_domain TEXT;
+|]
+
+down_m20260531_relay_sent_web_domain :: Text
+down_m20260531_relay_sent_web_domain =
+  [r|
+ALTER TABLE groups DROP COLUMN relay_sent_web_domain;
+|]

src/Simplex/Chat/Store/Postgres/Migrations/M20260531_relay_sent_web_url.hs

@@ -1,19 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE QuasiQuotes #-}
-
-module Simplex.Chat.Store.Postgres.Migrations.M20260531_relay_sent_web_url where
-
-import Data.Text (Text)
-import Text.RawString.QQ (r)
-
-m20260531_relay_sent_web_url :: Text
-m20260531_relay_sent_web_url =
-  [r|
-ALTER TABLE groups ADD COLUMN relay_sent_web_url TEXT;
-|]
-
-down_m20260531_relay_sent_web_url :: Text
-down_m20260531_relay_sent_web_url =
-  [r|
-ALTER TABLE groups DROP COLUMN relay_sent_web_url;
-|]

src/Simplex/Chat/Store/SQLite/Migrations.hs

@@ -158,7 +158,7 @@ import Simplex.Chat.Store.SQLite.Migrations.M20260515_public_group_access
 import Simplex.Chat.Store.SQLite.Migrations.M20260529_delivery_job_senders
 import Simplex.Chat.Store.SQLite.Migrations.M20260530_client_services
 import Simplex.Chat.Store.SQLite.Migrations.M20260531_member_removed_at
-import Simplex.Chat.Store.SQLite.Migrations.M20260531_relay_sent_web_url
+import Simplex.Chat.Store.SQLite.Migrations.M20260531_relay_sent_web_domain
 import Simplex.Messaging.Agent.Store.Shared (Migration (..))
 
 schemaMigrations :: [(String, Query, Maybe Query)]
@@ -317,7 +317,7 @@ schemaMigrations =
     ("20260529_delivery_job_senders", m20260529_delivery_job_senders, Just down_m20260529_delivery_job_senders),
     ("20260530_client_services", m20260530_client_services, Just down_m20260530_client_services),
     ("20260531_member_removed_at", m20260531_member_removed_at, Just down_m20260531_member_removed_at),
-    ("20260531_relay_sent_web_url", m20260531_relay_sent_web_url, Just down_m20260531_relay_sent_web_url)
+    ("20260531_relay_sent_web_domain", m20260531_relay_sent_web_domain, Just down_m20260531_relay_sent_web_domain)
   ]
 
 -- | The list of migrations in ascending order by date

src/Simplex/Chat/Store/SQLite/Migrations/M20260531_relay_sent_web_domain.hs

@@ -0,0 +1,18 @@
+{-# LANGUAGE QuasiQuotes #-}
+
+module Simplex.Chat.Store.SQLite.Migrations.M20260531_relay_sent_web_domain where
+
+import Database.SQLite.Simple (Query)
+import Database.SQLite.Simple.QQ (sql)
+
+m20260531_relay_sent_web_domain :: Query
+m20260531_relay_sent_web_domain =
+  [sql|
+ALTER TABLE groups ADD COLUMN relay_sent_web_domain TEXT;
+|]
+
+down_m20260531_relay_sent_web_domain :: Query
+down_m20260531_relay_sent_web_domain =
+  [sql|
+ALTER TABLE groups DROP COLUMN relay_sent_web_domain;
+|]

src/Simplex/Chat/Store/SQLite/Migrations/M20260531_relay_sent_web_url.hs

@@ -1,18 +0,0 @@
-{-# LANGUAGE QuasiQuotes #-}
-
-module Simplex.Chat.Store.SQLite.Migrations.M20260531_relay_sent_web_url where
-
-import Database.SQLite.Simple (Query)
-import Database.SQLite.Simple.QQ (sql)
-
-m20260531_relay_sent_web_url :: Query
-m20260531_relay_sent_web_url =
-  [sql|
-ALTER TABLE groups ADD COLUMN relay_sent_web_url TEXT;
-|]
-
-down_m20260531_relay_sent_web_url :: Query
-down_m20260531_relay_sent_web_url =
-  [sql|
-ALTER TABLE groups DROP COLUMN relay_sent_web_url;
-|]

src/Simplex/Chat/View.hs

@@ -1206,8 +1206,8 @@ viewReceivedContactRequest c Profile {fullName, shortDescr} =
   ]
 
 showRelay :: GroupRelay -> StyledString
-showRelay GroupRelay {groupRelayId, relayStatus, relayCap = RelayCapabilities {baseWebUrl}} =
-  "  - relay id " <> sShow groupRelayId <> ": " <> plain (relayStatusText relayStatus) <> maybe "" (\url -> ", web: " <> plain url) baseWebUrl
+showRelay GroupRelay {groupRelayId, relayStatus, relayCap = RelayCapabilities {webDomain}} =
+  "  - relay id " <> sShow groupRelayId <> ": " <> plain (relayStatusText relayStatus) <> maybe "" (\d -> ", web: " <> plain d) webDomain
 
 viewGroupRelays :: GroupInfo -> [GroupRelay] -> [StyledString]
 viewGroupRelays g relays =

src/Simplex/Chat/Web.hs

@@ -227,6 +227,9 @@ corsEntry publicGroupId PublicGroupAccess {groupWebPage, allowEmbedding} =
         | otherwise = CorsOrigins []
    in (fName, origin)
 
+channelPath :: Text
+channelPath = "/channel/"
+
 writeCorsConfig :: [(Text, CorsOrigin)] -> FilePath -> IO ()
 writeCorsConfig entries path =
   TIO.writeFile path $ T.unlines $
@@ -234,15 +237,15 @@ writeCorsConfig entries path =
     <> map corsLine entries
     <> [ "    default \"\"",
          "}",
-         "header /preview/*.json Access-Control-Allow-Origin {cors_origin}",
-         "header /preview/*.json Access-Control-Allow-Methods \"GET, OPTIONS\""
+         "header " <> channelPath <> "*.json Access-Control-Allow-Origin {cors_origin}",
+         "header " <> channelPath <> "*.json Access-Control-Allow-Methods \"GET, OPTIONS\""
        ]
   where
     corsLine (fName, origin) = case origin of
-      CorsAny -> "    /preview/" <> fName <> " \"*\""
+      CorsAny -> "    " <> channelPath <> fName <> " \"*\""
       CorsOrigins origins -> case origins of
         [] -> "    # " <> fName <> " (no origin configured)"
-        (o : _) -> "    /preview/" <> fName <> " \"" <> o <> "\""
+        (o : _) -> "    " <> channelPath <> fName <> " \"" <> o <> "\""
 
 publicGroupIdFileName :: B64UrlByteString -> String
 publicGroupIdFileName = B.unpack . strEncode

tests/ChatClient.hs

@@ -165,7 +165,7 @@ relayTestOpts :: ChatOpts
 relayTestOpts = testOpts {coreOptions = testCoreOpts {chatRelay = True}}
 
 relayWebTestOpts :: Text -> FilePath -> ChatOpts
-relayWebTestOpts webUrl webDir = testOpts {coreOptions = testCoreOpts {chatRelay = True, webPreviewConfig = Just WebPreviewConfig {baseWebUrl = webUrl, webJsonDir = webDir, webCorsFile = Nothing, webUpdateInterval = 300}}}
+relayWebTestOpts webDomain webDir = testOpts {coreOptions = testCoreOpts {chatRelay = True, webPreviewConfig = Just WebPreviewConfig {webDomain, webJsonDir = webDir, webCorsFile = Nothing, webUpdateInterval = 300}}}
 
 #if !defined(dbPostgres)
 getTestOpts :: Bool -> ScrubbedBytes -> ChatOpts

tests/ChatTests/ChatRelays.hs

@@ -35,7 +35,7 @@ chatRelayTests = do
     it "test chat relay" testChatRelayTest
     it "relay profile updated in address" testRelayProfileUpdateInAddress
   describe "relay capabilities" $ do
-    it "relay sends baseWebUrl in capabilities" testRelayWebCapabilities
+    it "relay sends webDomain in capabilities" testRelayWebCapabilities
   describe "web preview" $ do
     it "render web preview JSON for channel" testWebPreviewRender
     it "generate CORS config" testWebPreviewCors
@@ -339,7 +339,7 @@ getTermLine2 c = (,) <$> getTermLine c <*> getTermLine c
 testRelayWebCapabilities :: HasCallStack => TestParams -> IO ()
 testRelayWebCapabilities ps =
   withNewTestChat ps "alice" aliceProfile $ \alice ->
-    withNewTestChatOpts ps (relayWebTestOpts "https://relay.example.com/preview" (tmpPath ps </> "web_cap")) "bob" bobProfile $ \relay -> do
+    withNewTestChatOpts ps (relayWebTestOpts "relay.example.com" (tmpPath ps </> "web_cap")) "bob" bobProfile $ \relay -> do
       rName <- userName relay
       relay ##> "/ad"
       (relaySLink, _cLink) <- getContactLinks relay True
@@ -351,7 +351,7 @@ testRelayWebCapabilities ps =
       concurrentlyN_
         [ do
             alice <## "#news: group link relays updated, current relays:"
-            alice <## "  - relay id 1: active, web: https://relay.example.com/preview"
+            alice <## "  - relay id 1: active, web: relay.example.com"
             alice <## "group link:"
             _ <- getTermLine alice
             pure (),
@@ -362,7 +362,7 @@ testWebPreviewRender :: HasCallStack => TestParams -> IO ()
 testWebPreviewRender ps = do
   let webDir = tmpPath ps </> "web_preview"
   withNewTestChat ps "alice" aliceProfile $ \alice ->
-    withNewTestChatOpts ps (relayWebTestOpts "https://relay.example.com/preview" webDir) "bob" bobProfile $ \relay -> do
+    withNewTestChatOpts ps (relayWebTestOpts "relay.example.com" webDir) "bob" bobProfile $ \relay -> do
       _ <- setupRelay alice relay
       alice ##> "/public group relays=1 #news"
       alice <## "group #news is created"
@@ -370,7 +370,7 @@ testWebPreviewRender ps = do
       concurrentlyN_
         [ do
             alice <## "#news: group link relays updated, current relays:"
-            alice <## "  - relay id 1: active, web: https://relay.example.com/preview"
+            alice <## "  - relay id 1: active, web: relay.example.com"
             alice <## "group link:"
             _ <- getTermLine alice
             pure (),
@@ -411,8 +411,8 @@ testWebPreviewCors ps = do
         ]
   writeCorsConfig entries corsFile
   corsContent <- readFile corsFile
-  corsContent `shouldContain` "/preview/abc123.json \"*\""
-  corsContent `shouldContain` "/preview/def456.json \"https://owner-site.com\""
+  corsContent `shouldContain` "/channel/abc123.json \"*\""
+  corsContent `shouldContain` "/channel/def456.json \"https://owner-site.com\""
   corsContent `shouldContain` "# ghi789.json (no origin configured)"
   corsContent `shouldContain` "Access-Control-Allow-Origin"
 

website/src/js/channel-preview.jsc

@@ -432,12 +432,12 @@ const VOICE_ICON_SVG = `<svg class="simplex-preview-file-icon" viewBox="0 0 24 2
 const FORWARD_ICON_SVG = `<svg width="14" height="14" viewBox="0 -960 960 960" fill="currentColor"><path transform="scale(-1,1) translate(-960,0)" d="m236.5-495.5 142.5 143q8.5 8.5 8.25 20.25T378.5-312q-9 8.5-21 8.5t-20.5-9L145.5-504q-9-8.5-9-20t9-20.5L338-737q9-9 20.75-8.75T379.5-737q8.5 8.5 8.5 20.5t-8.5 20.5l-143 143h403q84 0 139.75 56T835-357.5V-234q0 12.5-8.25 20.75T806.5-205q-12.5 0-20.75-8.25T777.5-234v-123.5q0-60-39-99t-99-39h-403Z"/></svg>`;
 
 function initChannelPreview(container) {
-  const relayUrls = (container.dataset.relayUrls || '').split(',').map(u => u.trim()).filter(Boolean);
+  const relayDomains = (container.dataset.relayDomains || '').split(',').map(u => u.trim()).filter(Boolean);
   const groupId = container.dataset.publicGroupId || '';
   const groupLink = container.dataset.groupLink || '';
 
-  if (!relayUrls.length || !groupId) {
-    container.innerHTML = '<p class="simplex-preview-empty">Missing configuration: data-relay-urls and data-public-group-id required.</p>';
+  if (!relayDomains.length || !groupId) {
+    container.innerHTML = '<p class="simplex-preview-empty">Missing configuration: data-relay-domains and data-public-group-id required.</p>';
     return;
   }
 
@@ -445,7 +445,7 @@ function initChannelPreview(container) {
   container.classList.add('simplex-preview-container');
   container.innerHTML = '<p class="simplex-preview-empty">Loading channel...</p>';
 
-  fetchPreview(relayUrls, groupId).then(data => {
+  fetchPreview(relayDomains, groupId).then(data => {
     if (!data) {
       container.innerHTML = '<p class="simplex-preview-empty">Failed to load channel preview.</p>';
       return;
@@ -463,10 +463,10 @@ function injectStyles() {
   document.head.appendChild(style);
 }
 
-async function fetchPreview(relayUrls, groupId) {
-  for (const baseUrl of relayUrls) {
+async function fetchPreview(relayDomains, groupId) {
+  for (const domain of relayDomains) {
     try {
-      const url = baseUrl.replace(/\/$/, '') + '/' + groupId + '.json';
+      const url = `https://${domain}/channel/${groupId}.json`;
       const resp = await fetch(url);
       if (!resp.ok) continue;
       return await resp.json();