fix: page keys scroll pane scrollback at zsh and REPL prompts

src/app/input/terminal.rs

@@ -1971,4 +1971,42 @@ mod tests {
             .expect("scroll metrics after PageUp");
         assert_eq!(end_metrics.offset_from_bottom, 0);
     }
+
+    #[tokio::test]
+    async fn page_up_scrolls_shell_like_decckm_with_bracketed_paste() {
+        let mut app = app_for_mouse_test();
+        let mut ws = Workspace::test_new("test");
+        let pane_id = ws.tabs[0].root_pane;
+        let pane_infos = ws.tabs[0].layout.panes(Rect::new(26, 2, 80, 18));
+        let info = pane_infos[0].clone();
+        // zsh enables DECCKM via smkx and bracketed paste together; bash/fish do not.
+        let mut bytes = b"\x1b[?1h\x1b[?2004h".to_vec();
+        bytes.extend_from_slice(&numbered_lines_bytes(64));
+        let (runtime, mut input_rx) =
+            crate::terminal::TerminalRuntime::test_with_channel_and_scrollback_bytes(
+                info.inner_rect.width,
+                info.inner_rect.height,
+                16 * 1024,
+                &bytes,
+                4,
+            );
+        ws.tabs[0].runtimes.insert(pane_id, runtime);
+
+        app.state.workspaces = vec![ws];
+        app.state.active = Some(0);
+        app.state.selected = 0;
+        app.state.mode = Mode::Terminal;
+        app.state.view.pane_infos = pane_infos;
+
+        app.handle_terminal_key_headless(TerminalKey::new(KeyCode::PageUp, KeyModifiers::empty()));
+
+        assert!(
+            input_rx.try_recv().is_err(),
+            "PageUp should not reach the shell"
+        );
+        assert_eq!(
+            pane_scroll_offset(&app, pane_id),
+            info.inner_rect.height as usize
+        );
+    }
 }

src/pane/terminal.rs

@@ -130,7 +130,11 @@ impl InputState {
     }
 
     pub fn plain_page_keys_use_host_scrollback(self) -> bool {
-        !self.alternate_screen && !self.mouse_reporting_enabled() && !self.application_cursor
+        !self.alternate_screen
+            && !self.mouse_reporting_enabled()
+            // Bracketed paste distinguishes zsh's line editor (where it's on)
+            // from e.g. less -X (where it's off).
+            && (!self.application_cursor || self.bracketed_paste)
     }
 }
 
@@ -3073,6 +3077,21 @@ mod tests {
     use ratatui::{layout::Rect, style::Color};
     use tokio::sync::mpsc;
 
+    #[test]
+    fn plain_page_keys_host_scroll_for_shell_like_decckm_with_bracketed_paste() {
+        assert!(InputState {
+            alternate_screen: false,
+            application_cursor: true,
+            bracketed_paste: true,
+            focus_reporting: false,
+            mouse_protocol_mode: crate::input::MouseProtocolMode::None,
+            mouse_protocol_encoding: crate::input::MouseProtocolEncoding::Default,
+            mouse_alternate_scroll: false,
+            modify_other_keys: false,
+        }
+        .plain_page_keys_use_host_scrollback());
+    }
+
     fn text_cell(text: &str) -> crate::ghostty::ScreenTextCell {
         crate::ghostty::ScreenTextCell {
             wide: crate::ghostty::CellWide::Narrow,

src/server/headless.rs

@@ -6468,6 +6468,22 @@ next_tab = ""
         });
     }
 
+    #[test]
+    fn terminal_attach_page_key_host_scrolls_shell_like_decckm_with_bracketed_paste() {
+        with_terminal_attach_page_key_runtime(b"\x1b[?1h\x1b[?2004h", 0, |runtime, input_rx| {
+            apply_terminal_attach_page_up(runtime);
+
+            assert_eq!(
+                runtime
+                    .scroll_metrics()
+                    .expect("scroll metrics")
+                    .offset_from_bottom,
+                4
+            );
+            assert!(input_rx.try_recv().is_err());
+        });
+    }
+
     #[test]
     fn terminal_attach_page_key_forwards_in_alternate_screen_without_mouse_reporting() {
         with_terminal_attach_page_key_runtime(b"\x1b[?1049h", 3, |runtime, input_rx| {