jump to next attention item

mac/Sources/Byre/Chat.swift

@@ -337,14 +337,27 @@ final class ChatModel {
         return groups
     }
 
-    var held: Int? {
+    var attentionRows: [Int] {
         let ids = Set(attention().flatMap(\.rows))
-        guard let first = builder.root.rows.first(where: { ids.contains($0.id) })?.id, first != released else {
+        return builder.root.rows.filter { ids.contains($0.id) }.map(\.id)
+    }
+
+    var held: Int? {
+        guard let first = attentionRows.first, first != released else {
             return nil
         }
         return first
     }
 
+    func closed(_ old: [Int], _ new: [Int]) {
+        guard let gone = old.first(where: { !new.contains($0) }), let first = new.first else {
+            return
+        }
+        let rows = builder.root.rows
+        let at = rows.firstIndex { $0.id == gone } ?? rows.endIndex
+        scrollTo(rows[at...].first { new.contains($0.id) }?.id ?? first)
+    }
+
     func release() {
         released = held ?? released
     }
@@ -812,6 +825,9 @@ private struct TranscriptScroll: View {
                 position.scrollTo(edge: .bottom)
             }
         }
+        .onChange(of: model.attentionRows) { old, new in
+            model.closed(old, new)
+        }
         .onChange(of: model.older == nil) {
             if !scrolling {
                 model.prependOlder()