diff --git a/docs/architecture.md b/docs/architecture.md
index 35b4707..fdac98a 100644
--- a/docs/architecture.md
+++ b/docs/architecture.md
@@ -40,6 +40,8 @@ Architect is a terminal multiplexer displaying interactive sessions in a grid wi
 8. Calls `renderer.render` for the scene, then `ui.render` for overlays, then presents.
 9. Sleeps based on idle/active frame targets (~16ms active, ~50ms idle).
 
+`SessionState.dirty` is set on terminal updates and cleared after a successful render (cached grid or full view). When collapsing from full view to grid, the focused session is marked dirty so its cache refreshes before idle throttling resumes.
+
 **Terminal resizing**
 - `applyTerminalResize` updates the PTY size first, then resizes the `ghostty-vt` terminal.
 - The VT stream stays alive; only its handler is refreshed to repoint at the resized terminal, preserving parser state and preventing in-flight escape sequences from being misparsed.
diff --git a/src/main.zig b/src/main.zig
index f9465a7..67fac9a 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -1321,11 +1321,16 @@ pub fn main() !void {
             anim_state.mode == .PanningUp or anim_state.mode == .PanningDown)
         {
             if (anim_state.isComplete(now)) {
-                anim_state.mode = switch (anim_state.mode) {
+                const previous_mode = anim_state.mode;
+                const next_mode = switch (anim_state.mode) {
                     .Expanding, .PanningLeft, .PanningRight, .PanningUp, .PanningDown => .Full,
                     .Collapsing => .Grid,
                     else => anim_state.mode,
                 };
+                anim_state.mode = next_mode;
+                if (previous_mode == .Collapsing and next_mode == .Grid and anim_state.focused_session < sessions.len) {
+                    sessions[anim_state.focused_session].dirty = true;
+                }
                 std.debug.print("Animation complete, new mode: {s}\n", .{@tagName(anim_state.mode)});
             }
         }
diff --git a/src/render/renderer.zig b/src/render/renderer.zig
index b88cf11..4de53dc 100644
--- a/src/render/renderer.zig
+++ b/src/render/renderer.zig
@@ -154,6 +154,7 @@ fn renderSession(
 ) RenderError!void {
     try renderSessionContent(renderer, session, rect, scale, is_focused, font, term_cols, term_rows, theme);
     renderSessionOverlays(renderer, session, rect, is_focused, apply_effects, current_time_ms, is_grid_view, theme);
+    session.dirty = false;
 }
 
 fn renderSessionContent(