make sure that we always select the first channel if possible (#5725)

frontend/app/src/components/home/Home.svelte

@@ -387,6 +387,17 @@
         return found;
     }
 
+    function selectFirstChat(): boolean {
+        if (!$mobileWidth) {
+            const first = $chatSummariesListStore.find((c) => !c.membership.archived);
+            if (first !== undefined) {
+                page.redirect(routeForChatIdentifier($chatListScope.kind, first.id));
+                return true;
+            }
+        }
+        return false;
+    }
+
     // extracting to a function to try to control more tightly what this reacts to
     async function routeChange(initialised: boolean, pathParams: RouteParams): Promise<void> {
         // wait until we have loaded the chats
@@ -408,16 +419,8 @@
             }
 
             // When we have a middle panel and this route is for a chat list then select the first chat
-            if (
-                !$mobileWidth &&
-                (pathParams.kind === "selected_community_route" ||
-                    pathParams.kind === "chat_list_route")
-            ) {
-                const first = $chatSummariesListStore.find((c) => !c.membership.archived);
-                if (first !== undefined) {
-                    page.redirect(routeForChatIdentifier($chatListScope.kind, first.id));
-                    return;
-                }
+            if (pathParams.kind === "chat_list_route" && selectFirstChat()) {
+                return;
             }
 
             if (pathParams.kind === "home_route") {
@@ -429,6 +432,9 @@
                 rightPanelHistory.set($fullWidth ? [{ kind: "community_filters" }] : []);
             } else if (pathParams.kind === "selected_community_route") {
                 await selectCommunity(pathParams.communityId);
+                if (selectFirstChat()) {
+                    return;
+                }
             } else if (
                 pathParams.kind === "global_chat_selected_route" ||
                 pathParams.kind === "selected_channel_route"