From c8d9d04f59e9eafb96db314c0435d6cc18b446b2 Mon Sep 17 00:00:00 2001
From: Martino Ferrari <martinogiordano.ferrari@iter.org>
Date: Tue, 3 Nov 2026 10:47:11 +0100
Subject: [PATCH] ui: the readouts show in a strip under the plot when the dock
 is hidden

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 src/ui.cpp            |  11 ++-
 src/ui/main-window.ui |  26 ++++++-
 src/ui_app.hpp        |  18 +++++
 src/ui_cursors.cpp    |   5 +-
 src/ui_dock.cpp       | 154 +++++++++++++++++++++++++++++++++++++-----
 src/ui_probe.cpp      |  88 ++++++++++++++++++++++++
 src/ui_widgets.cpp    |   2 +
 7 files changed, 282 insertions(+), 22 deletions(-)

diff --git a/src/ui.cpp b/src/ui.cpp
index cd3aa0b..f768826 100644
--- a/src/ui.cpp
+++ b/src/ui.cpp
@@ -4013,6 +4013,11 @@ gboolean tick(gpointer user) {
         app->sidebar_syncing = false;
       }
     }
+    // The readouts strip is on screen exactly when the dock is not. Decided here, right after the wish was
+    // re-asserted and *before* the collapsing below (which makes the split view write `show-sidebar`
+    // false itself until the next frame re-asserts it): read after it, the strip would show for one frame
+    // each time the window narrowed.
+    sync_readouts_strip(*app);
     const int window_w = gtk_widget_get_width(app->window);
     if (window_w > 0) {
       adw_overlay_split_view_set_collapsed(ADW_OVERLAY_SPLIT_VIEW(app->side_view),
@@ -4976,6 +4981,8 @@ void on_activate(GtkApplication* application, gpointer user) {
   app->badge_bar = GTK_WIDGET(gtk_builder_get_object(app->window_ui, "badge_bar"));
   app->badge_signals = GTK_WIDGET(gtk_builder_get_object(app->window_ui, "badge_signals"));
   app->badge_system = GTK_WIDGET(gtk_builder_get_object(app->window_ui, "badge_system"));
+  app->readouts_strip = GTK_WIDGET(gtk_builder_get_object(app->window_ui, "readouts_strip"));
+  app->strip_box = GTK_WIDGET(gtk_builder_get_object(app->window_ui, "readouts_strip_box"));
   // A missing id is the one mistake neither the build nor `GtkBuilder` sees, and every use below would
   // be a null pointer.
   if (app->window == nullptr || side_view == nullptr ||
@@ -4983,7 +4990,7 @@ void on_activate(GtkApplication* application, gpointer user) {
       app->status_badge == nullptr ||
       app->status_label == nullptr || app->status_info_button == nullptr ||
       app->status_row == nullptr || app->badge_bar == nullptr || app->badge_signals == nullptr ||
-      app->badge_system == nullptr ||
+      app->badge_system == nullptr || app->readouts_strip == nullptr || app->strip_box == nullptr ||
       side == nullptr || app->dock_scroller == nullptr || app->dock_page == nullptr) {
     return;
   }
@@ -5165,7 +5172,7 @@ void on_activate(GtkApplication* application, gpointer user) {
   // switch that turns it back on. The trigger's body is deliberately *not* disabled: a trigger is
   // configured before it is switched on, so its settings have to stay editable while it is off.
   gtk_widget_set_sensitive(app->cursors_body, FALSE);
-  gtk_widget_set_sensitive(app->dock_cursor_grid, FALSE);
+  dock_set_cursors_sensitive(*app, false);  // the dock's grid and the strip's chips, together
   // The arm controls are the one part of the trigger pane that needs trigger mode running: both of them,
   // and the compact line's visibility, are stated from the toggle by `sync_arm_buttons()`.
   sync_arm_buttons(*app);
diff --git a/src/ui/main-window.ui b/src/ui/main-window.ui
index 6817e15..8903bfe 100644
--- a/src/ui/main-window.ui
+++ b/src/ui/main-window.ui
@@ -4,7 +4,8 @@
 <!--
   The main window's skeleton: the window, the split view that puts the sidebar beside the plot, the
   plot column (`left_column`: `plot_overlay` > `plot_box`, the slide-over panel being an overlay child added
-  in code) with the badge bar and the status line under it, and the sidebar, which is the dock.
+  in code) with the readouts strip (only while the dock is not on screen), the badge bar and the status
+  line under it, and the sidebar, which is the dock.
 
   The sidebar is an `AdwOverlaySplitView`, which is what a utility sidebar is in GNOME (as against
   `AdwNavigationSplitView`, which is for navigation lists). Three things follow from that, and they are
@@ -96,6 +97,29 @@
                 </child>
               </object>
             </child>
+            <child>
+              <!-- The readouts strip: the cursors' deltas and the measurements' values on one line, shown
+                   only while the dock is not (hidden with the Dock button, or collapsed and not currently
+                   overlaid; `sync_readouts_strip()` decides, per tick). A fixed height, so the content
+                   never sets it; what does not fit scrolls horizontally with no bar taking height. The
+                   box inside is filled by code (`src/ui_dock.cpp`). Starts hidden: the dock starts shown. -->
+              <object class="GtkScrolledWindow" id="readouts_strip">
+                <property name="visible">0</property>
+                <property name="height-request">26</property>
+                <property name="vexpand">0</property>
+                <property name="hscrollbar-policy">external</property>
+                <property name="vscrollbar-policy">never</property>
+                <property name="margin-start">6</property>
+                <property name="margin-end">6</property>
+                <property name="child">
+                  <object class="GtkBox" id="readouts_strip_box">
+                    <property name="orientation">horizontal</property>
+                    <property name="spacing">8</property>
+                    <property name="valign">center</property>
+                  </object>
+                </property>
+              </object>
+            </child>
             <child>
               <!-- Setup is reached by the object it configures: a badge per signal on the left
                    (step 2), the system badges (Trigger, Source) on the right. A fixed height, so
diff --git a/src/ui_app.hpp b/src/ui_app.hpp
index 63cc958..f01210f 100644
--- a/src/ui_app.hpp
+++ b/src/ui_app.hpp
@@ -610,6 +610,17 @@ struct App {
   GtkWidget* dock_measures_edit = nullptr;
   /// One value label per measurement, in `measures` order (the dock's copy of `measure_labels`).
   std::vector<GtkWidget*> dock_measure_labels;
+  /// The readouts strip under the plot (`main-window.ui` `readouts_strip`, `src/ui_dock.cpp`): shown only
+  /// while the dock is not. Its value labels mirror the dock's one for one -- `strip_cursor_deltas` the
+  /// `d` cell of each `dock_cursor_lines` entry, `strip_measure_labels` each of `dock_measure_labels` --
+  /// and `strip_cursor_who` the cursor lines' `who` cells, all written from the dock setters' arguments.
+  GtkWidget* readouts_strip = nullptr;
+  GtkWidget* strip_box = nullptr;
+  GtkWidget* strip_cursor_box = nullptr;   ///< the cursor chips; insensitive with the cursors off
+  GtkWidget* strip_measure_box = nullptr;  ///< the measurement chips
+  std::vector<GtkWidget*> strip_cursor_who;
+  std::vector<GtkWidget*> strip_cursor_deltas;
+  std::vector<GtkWidget*> strip_measure_labels;
   /// The measurements the user set up, and what they last computed. The list is the state;
   /// the results are recomputed on a throttle (the numbers are window statistics, and the
   /// window scrolls every frame -- 60 recomputations a second of every sample is not a
@@ -1784,6 +1795,13 @@ void dock_rebuild_measures(App& app);
 void dock_cursor_cell(App& app, std::size_t line, const std::string& a, const std::string& b,
                       const std::string& d);
 void dock_measure_value(App& app, std::size_t i, const std::string& text);
+/// The readouts strip under the plot (`src/ui_dock.cpp`): the third reader of the same strings. It is
+/// filled by the `dock_*` rebuilds and written by the `dock_*` setters above (so nothing here formats),
+/// and shown exactly when the dock is not: `sync_readouts_strip()` is called by the tick after the
+/// show-sidebar reconciliation. `dock_set_cursors_sensitive()` is the one writer of the cursor readouts'
+/// sensitivity, for the dock's grid and the strip's chips together.
+void sync_readouts_strip(App& app);
+void dock_set_cursors_sensitive(App& app, bool on);
 /// The Events block under the readouts (`src/ui_dock.cpp`): compact rows (marker, title, time; no
 /// thumbnails) from `event_store->list()`, newest first, and a Manage button for the `events` page.
 /// `dock_rebuild_events()` follows every change of what is *cached*, `dock_mark_events()` every change
diff --git a/src/ui_cursors.cpp b/src/ui_cursors.cpp
index b604b61..be9bf33 100644
--- a/src/ui_cursors.cpp
+++ b/src/ui_cursors.cpp
@@ -151,8 +151,9 @@ void on_cursors_toggled(GtkToggleButton* button, gpointer user) {
   // cursors back on -- and a control inside an insensitive parent cannot be clicked.
   gtk_widget_set_sensitive(app->cursors_reset, on);
   if (app->cursors_body != nullptr) gtk_widget_set_sensitive(app->cursors_body, on);
-  // The dock's copy follows: switched off it stays on screen, insensitive, reading `--`.
-  if (app->dock_cursor_grid != nullptr) gtk_widget_set_sensitive(app->dock_cursor_grid, on);
+  // The dock's copy and the strip's chips follow: switched off they stay on screen, insensitive, reading
+  // `--`. One function, so the two cannot disagree.
+  dock_set_cursors_sensitive(*app, on);
   if (!on) update_cursors_pane(*app);
   if (on) {
     app->rows->reset_cursors();
diff --git a/src/ui_dock.cpp b/src/ui_dock.cpp
index b68ab6b..888bc6b 100644
--- a/src/ui_dock.cpp
+++ b/src/ui_dock.cpp
@@ -9,6 +9,12 @@
 // so the two views cannot disagree. Every label is ellipsized at a fixed `width-chars`, so the dock's
 // layout does not depend on what a value reads; the full text is the label's tooltip.
 //
+// The same strings are shown a third time in the readouts strip under the plot (`readouts_strip`, one
+// fixed-height line: a "Cursors" button, one chip per cursor line with its delta, a "Measures" button, one
+// chip per measurement with its value), which is on screen exactly when the dock is not. The setters below
+// write the strip's labels in the same call as the dock's, from the same argument, so there is still one
+// string and no second formatter.
+//
 // Below them, the Events block: one compact row per cached event (marker, title, time; no thumbnails),
 // a Manage button for the full list, and one click on a row to replay it. Its rows are built from the
 // same `event_store->list()` and the same `event_row_title()` as the events page, so the two cannot
@@ -72,6 +78,46 @@ void on_measure_line_pressed(GtkGestureClick* gesture, int n_press, double, doub
   open_measure_dialog(*static_cast<App*>(user), idx);
 }
 
+/// The page's `who` cell, verbatim, onto a copy: a chip and a name as markup, or plain text, and its
+/// tooltip. The dock's cell and the strip's chip are both made by it.
+void copy_who(GtkWidget* dst, GtkWidget* src) {
+  if (src == nullptr) return;
+  const char* text = gtk_label_get_label(GTK_LABEL(src));
+  if (gtk_label_get_use_markup(GTK_LABEL(src))) {
+    gtk_label_set_markup(GTK_LABEL(dst), text);
+  } else {
+    gtk_label_set_text(GTK_LABEL(dst), text);
+  }
+  const char* tip = gtk_widget_get_tooltip_text(src);
+  gtk_widget_set_tooltip_text(dst, tip != nullptr ? tip : gtk_label_get_text(GTK_LABEL(src)));
+}
+
+void clear_box(GtkWidget* box) {
+  GtkWidget* child = gtk_widget_get_first_child(box);
+  while (child != nullptr) {
+    GtkWidget* next = gtk_widget_get_next_sibling(child);
+    gtk_box_remove(GTK_BOX(box), child);
+    child = next;
+  }
+}
+
+/// The strip's cell widths, in characters. Fixed like the dock's, so the strip's chips are as wide with
+/// `--` as with `-123.456 mV` (what does not fit scrolls).
+constexpr int kStripWhoChars = 6;
+constexpr int kStripTypeChars = 10;
+
+/// A flat text button that opens a slide-over page. It only opens a page, so a rebuild can never free the
+/// widget its own signal was emitted from.
+GtkWidget* strip_button(const char* label, GCallback on_click, App* app, const char* tip) {
+  GtkWidget* b = gtk_button_new_with_label(label);
+  gtk_widget_add_css_class(b, "flat");
+  gtk_widget_add_css_class(b, "udpscope-strip-button");
+  gtk_widget_set_valign(b, GTK_ALIGN_CENTER);
+  gtk_widget_set_tooltip_text(b, tip);
+  g_signal_connect(b, "clicked", on_click, app);
+  return b;
+}
+
 /// A section's heading row: its title at the left, its Edit button at the right.
 GtkWidget* section_head(const char* title, GtkWidget** edit_out, GCallback on_edit, App* app,
                         const char* tip) {
@@ -101,6 +147,25 @@ void dock_cursors_header(GtkGrid* grid) {
   }
 }
 
+/// Fills the strip `main-window.ui` declares: the two buttons and the two boxes the rebuilds fill.
+void build_readouts_strip(App& app) {
+  if (app.strip_box == nullptr) return;
+  clear_box(app.strip_box);
+  app.strip_cursor_box = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 8);
+  app.strip_measure_box = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 8);
+  gtk_box_append(GTK_BOX(app.strip_box),
+                 strip_button("Cursors", G_CALLBACK(on_edit_cursors), &app, "the cursors' full panel"));
+  gtk_box_append(GTK_BOX(app.strip_box), app.strip_cursor_box);
+  GtkWidget* sep = gtk_separator_new(GTK_ORIENTATION_VERTICAL);
+  gtk_widget_set_margin_top(sep, 5);
+  gtk_widget_set_margin_bottom(sep, 5);
+  gtk_box_append(GTK_BOX(app.strip_box), sep);
+  gtk_box_append(GTK_BOX(app.strip_box),
+                 strip_button("Measures", G_CALLBACK(on_edit_measures), &app,
+                              "the measurements' full panel"));
+  gtk_box_append(GTK_BOX(app.strip_box), app.strip_measure_box);
+}
+
 }  // namespace
 
 GtkWidget* build_readouts_dock(App& app) {
@@ -130,6 +195,7 @@ GtkWidget* build_readouts_dock(App& app) {
   gtk_box_append(GTK_BOX(box), app.dock_measures_box);
 
   app.dock_readouts = box;
+  build_readouts_strip(app);
   // The tables are built from the pages' current lines, which exist already when the pages were built
   // first; otherwise the pages' own rebuild fills them.
   dock_rebuild_cursors(app);
@@ -147,22 +213,17 @@ void dock_rebuild_cursors(App& app) {
     child = next;
   }
   app.dock_cursor_lines.clear();
+  // The strip's chips are rebuilt with the dock's lines (one per line, same order), so the counts agree by
+  // construction. The box itself keeps its sensitivity across the rebuild.
+  if (app.strip_cursor_box != nullptr) clear_box(app.strip_cursor_box);
+  app.strip_cursor_who.clear();
+  app.strip_cursor_deltas.clear();
   dock_cursors_header(grid);
   int at = 1;
   for (const App::CursorLine& src : app.cursors_lines) {
     App::DockCursorLine line;
     line.label = fixed_label("", kNameChars, GTK_ALIGN_START);
-    if (src.label != nullptr) {
-      // The page's `who` cell, verbatim: a chip and a name as markup, or plain text.
-      const char* text = gtk_label_get_label(GTK_LABEL(src.label));
-      if (gtk_label_get_use_markup(GTK_LABEL(src.label))) {
-        gtk_label_set_markup(GTK_LABEL(line.label), text);
-      } else {
-        gtk_label_set_text(GTK_LABEL(line.label), text);
-      }
-      const char* tip = gtk_widget_get_tooltip_text(src.label);
-      gtk_widget_set_tooltip_text(line.label, tip != nullptr ? tip : gtk_label_get_text(GTK_LABEL(src.label)));
-    }
+    copy_who(line.label, src.label);
     gtk_grid_attach(grid, line.label, 0, at, 1, 1);
     GtkWidget** cells[3] = {&line.a, &line.b, &line.d};
     for (int c = 0; c < 3; ++c) {
@@ -173,25 +234,41 @@ void dock_rebuild_cursors(App& app) {
       *cells[c] = v;
     }
     app.dock_cursor_lines.push_back(line);
+    if (app.strip_cursor_box != nullptr) {
+      // A chip: the line's `who` and its delta. Not selectable, so a drag on it scrolls the strip.
+      GtkWidget* chip = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 4);
+      GtkWidget* who = fixed_label("", kStripWhoChars, GTK_ALIGN_START);
+      copy_who(who, src.label);
+      GtkWidget* delta = fixed_label("", kValueChars, GTK_ALIGN_END);
+      gtk_widget_add_css_class(delta, "numeric");
+      gtk_box_append(GTK_BOX(chip), who);
+      gtk_box_append(GTK_BOX(chip), delta);
+      gtk_box_append(GTK_BOX(app.strip_cursor_box), chip);
+      app.strip_cursor_who.push_back(who);
+      app.strip_cursor_deltas.push_back(delta);
+    }
     ++at;
   }
 }
 
 void dock_rebuild_measures(App& app) {
   if (app.dock_measures_box == nullptr) return;
-  GtkWidget* child = gtk_widget_get_first_child(app.dock_measures_box);
-  while (child != nullptr) {
-    GtkWidget* next = gtk_widget_get_next_sibling(child);
-    gtk_box_remove(GTK_BOX(app.dock_measures_box), child);
-    child = next;
-  }
+  clear_box(app.dock_measures_box);
+  if (app.strip_measure_box != nullptr) clear_box(app.strip_measure_box);
   app.dock_measure_labels.clear();
+  app.strip_measure_labels.clear();
   if (app.measures.empty()) {
     GtkWidget* none = gtk_label_new("no measurements");
     gtk_widget_set_halign(none, GTK_ALIGN_START);
     gtk_widget_add_css_class(none, "caption");
     gtk_widget_add_css_class(none, "dim-label");
     gtk_box_append(GTK_BOX(app.dock_measures_box), none);
+    if (app.strip_measure_box != nullptr) {
+      GtkWidget* strip_none = gtk_label_new("no measurements");
+      gtk_widget_add_css_class(strip_none, "caption");
+      gtk_widget_add_css_class(strip_none, "dim-label");
+      gtk_box_append(GTK_BOX(app.strip_measure_box), strip_none);
+    }
     return;
   }
   for (std::size_t i = 0; i < app.measures.size(); ++i) {
@@ -217,6 +294,29 @@ void dock_rebuild_measures(App& app) {
     gtk_widget_add_controller(line, GTK_EVENT_CONTROLLER(click));
     gtk_box_append(GTK_BOX(app.dock_measures_box), line);
     app.dock_measure_labels.push_back(value);
+
+    if (app.strip_measure_box != nullptr) {
+      // The strip's chip: the signal's chip, the type's short name and the value; a click on it opens the
+      // same dialog as the dock's line.
+      GtkWidget* sline = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 4);
+      g_object_set_data(G_OBJECT(sline), "udpscope-measure-index",
+                        GINT_TO_POINTER(static_cast<int>(i) + 1));
+      GtkWidget* schip = gtk_label_new("");
+      gtk_label_set_markup(GTK_LABEL(schip), measure_chip_markup(app, m.signal).c_str());
+      gtk_widget_set_tooltip_text(schip, m.signal.c_str());
+      gtk_box_append(GTK_BOX(sline), schip);
+      GtkWidget* skind = fixed_label(measure_type_name(m.type), kStripTypeChars, GTK_ALIGN_START);
+      gtk_widget_set_tooltip_text(skind, (m.signal + "\n" + measure_type_name(m.type)).c_str());
+      gtk_box_append(GTK_BOX(sline), skind);
+      GtkWidget* svalue = fixed_label("--", kValueChars, GTK_ALIGN_END);
+      gtk_widget_add_css_class(svalue, "numeric");
+      gtk_box_append(GTK_BOX(sline), svalue);
+      GtkGesture* sclick = gtk_gesture_click_new();
+      g_signal_connect(sclick, "pressed", G_CALLBACK(on_measure_line_pressed), &app);
+      gtk_widget_add_controller(sline, GTK_EVENT_CONTROLLER(sclick));
+      gtk_box_append(GTK_BOX(app.strip_measure_box), sline);
+      app.strip_measure_labels.push_back(svalue);
+    }
   }
 }
 
@@ -227,11 +327,31 @@ void dock_cursor_cell(App& app, std::size_t line, const std::string& a, const st
   set_value_text(l.a, a);
   set_value_text(l.b, b);
   set_value_text(l.d, d);
+  // The strip's chip takes the delta from the same argument, in the same call.
+  if (line < app.strip_cursor_deltas.size()) set_value_text(app.strip_cursor_deltas[line], d);
 }
 
 void dock_measure_value(App& app, std::size_t i, const std::string& text) {
   if (i >= app.dock_measure_labels.size()) return;  // mid-rebuild
   set_value_text(app.dock_measure_labels[i], text);
+  if (i < app.strip_measure_labels.size()) set_value_text(app.strip_measure_labels[i], text);
+}
+
+void dock_set_cursors_sensitive(App& app, bool on) {
+  // Disabled, not hidden: the dock's grid and the strip's chips go grey together and read `--`.
+  if (app.dock_cursor_grid != nullptr) gtk_widget_set_sensitive(app.dock_cursor_grid, on);
+  if (app.strip_cursor_box != nullptr) gtk_widget_set_sensitive(app.strip_cursor_box, on);
+}
+
+void sync_readouts_strip(App& app) {
+  if (app.readouts_strip == nullptr || app.side_view == nullptr) return;
+  // The strip is on screen exactly when the dock is not: `show-sidebar` is false when the dock is hidden
+  // with the Dock button, and when the window is collapsed and the dock is not currently overlaid.
+  const bool want =
+      !adw_overlay_split_view_get_show_sidebar(ADW_OVERLAY_SPLIT_VIEW(app.side_view));
+  if ((gtk_widget_get_visible(app.readouts_strip) != FALSE) != want) {
+    gtk_widget_set_visible(app.readouts_strip, want);
+  }
 }
 
 namespace {
diff --git a/src/ui_probe.cpp b/src/ui_probe.cpp
index 6939297..6e2c5a9 100644
--- a/src/ui_probe.cpp
+++ b/src/ui_probe.cpp
@@ -4337,6 +4337,90 @@ static int dock_width_fits(App& a, int* dock_w, int* side_w) {
   return *dock_w >= 0 && *side_w > 0 && *dock_w <= *side_w ? 1 : 0;
 }
 
+/// The readouts strip against the dock it mirrors: `same_text=1` when every strip label's text equals the
+/// dock's (the cursors' `who` and delta cells, the measurements' values) and the counts agree. `visible` must
+/// be the opposite of `dock_shown` (`show-sidebar`), and `h` the strip's fixed 26 whenever it is visible.
+/// `sens_same` is the strip's cursor chips sharing the dock grid's sensitivity.
+static void strip_report(App& a, const char* tag, const char* what) {
+  const auto text = [](GtkWidget* w) { return std::string(gtk_label_get_text(GTK_LABEL(w))); };
+  int same = a.strip_cursor_deltas.size() == a.dock_cursor_lines.size() &&
+                     a.strip_cursor_who.size() == a.dock_cursor_lines.size() &&
+                     a.strip_measure_labels.size() == a.dock_measure_labels.size()
+                 ? 1 : 0;
+  for (std::size_t i = 0; same != 0 && i < a.dock_cursor_lines.size(); ++i) {
+    if (text(a.strip_cursor_deltas[i]) != text(a.dock_cursor_lines[i].d) ||
+        text(a.strip_cursor_who[i]) != text(a.dock_cursor_lines[i].label)) {
+      same = 0;
+    }
+  }
+  for (std::size_t i = 0; same != 0 && i < a.dock_measure_labels.size(); ++i) {
+    if (text(a.strip_measure_labels[i]) != text(a.dock_measure_labels[i])) same = 0;
+  }
+  const bool dock_shown =
+      a.side_view != nullptr &&
+      adw_overlay_split_view_get_show_sidebar(ADW_OVERLAY_SPLIT_VIEW(a.side_view)) != FALSE;
+  const bool visible = a.readouts_strip != nullptr && gtk_widget_get_visible(a.readouts_strip);
+  const bool collapsed =
+      a.side_view != nullptr &&
+      adw_overlay_split_view_get_collapsed(ADW_OVERLAY_SPLIT_VIEW(a.side_view)) != FALSE;
+  const bool sens_same =
+      a.strip_cursor_box != nullptr && a.dock_cursor_grid != nullptr &&
+      gtk_widget_get_sensitive(a.strip_cursor_box) == gtk_widget_get_sensitive(a.dock_cursor_grid);
+  std::fprintf(stderr,
+               "[%s-probe] %-14s strip: visible=%d dock_shown=%d cursors=%zu measures=%zu same_text=%d "
+               "h=%d sens_same=%d collapsed=%d window=%d\n",
+               tag, what, visible ? 1 : 0, dock_shown ? 1 : 0, a.strip_cursor_deltas.size(),
+               a.strip_measure_labels.size(), same, a.readouts_strip != nullptr
+                   ? gtk_widget_get_height(a.readouts_strip) : -1,
+               sens_same ? 1 : 0, collapsed ? 1 : 0,
+               a.window != nullptr ? gtk_widget_get_width(a.window) : -1);
+}
+
+/// Puts the dock away through the wish the tick re-asserts and reads the strip with it hidden
+/// (`<tag>-probe ... strip:`: visible must be 1, h 26, same_text 1), then restores the wish and reads it
+/// again (visible must be 0). Under `xvfb-run` the window is 756 px wide, below `kSidebarRoom`, so the split
+/// view is `collapsed` on every line: both legs are the collapsed case (the tick keeps a wished dock
+/// overlaid, a hidden one off), and `collapsed=0` is not reachable from a probe -- a window with no
+/// manager cannot be resized by `gtk_window_set_default_size()`.
+struct StripDrive {
+  App* app;
+  const char* tag;
+  int step;
+};
+
+static gboolean strip_drive_step(gpointer user) {
+  auto* d = static_cast<StripDrive*>(user);
+  App& a = *d->app;
+  if (a.window == nullptr) {
+    delete d;
+    return G_SOURCE_REMOVE;
+  }
+  switch (d->step) {
+    case 0:
+      a.sidebar_wanted = false;
+      update_side_visibility(a);
+      break;
+    case 1:
+      strip_report(a, d->tag, "dock hidden");
+      a.sidebar_wanted = true;
+      update_side_visibility(a);
+      break;
+    default:
+      strip_report(a, d->tag, "dock restored");
+      std::fflush(stderr);
+      delete d;
+      return G_SOURCE_REMOVE;
+  }
+  std::fflush(stderr);
+  ++d->step;
+  g_timeout_add(600, strip_drive_step, d);
+  return G_SOURCE_REMOVE;
+}
+
+static void strip_drive(App& a, const char* tag) {
+  g_timeout_add(100, strip_drive_step, new StripDrive{&a, tag, 0});
+}
+
 static void dock_cursors_report(App& a, const char* what) {
   int same = a.dock_cursor_lines.size() == a.cursors_lines.size() ? 1 : 0;
   for (std::size_t i = 0; same != 0 && i < a.cursors_lines.size(); ++i) {
@@ -4356,6 +4440,7 @@ static void dock_cursors_report(App& a, const char* what) {
                "side_w=%d fits=%d dock_sensitive=%d\n",
                what, a.dock_cursor_lines.size(), a.cursors_lines.size(), same, dock_w, side_w, fits,
                a.dock_cursor_grid != nullptr && gtk_widget_get_sensitive(a.dock_cursor_grid) ? 1 : 0);
+  strip_report(a, "cursors", what);
 }
 
 static void dock_measures_report(App& a, const char* what) {
@@ -4374,6 +4459,7 @@ static void dock_measures_report(App& a, const char* what) {
                "side_w=%d fits=%d\n",
                what, a.dock_measure_labels.size(), a.measure_labels.size(), same, dock_w, side_w,
                fits);
+  strip_report(a, "measures", what);
 }
 
 void cursors_probe_report(App& a, const char* what) {
@@ -4646,6 +4732,7 @@ gboolean cursors_probe_step(gpointer user) {
     }
     default:
       cursors_probe_report(*a, "after ruler drag");
+      strip_drive(*a, "cursors");  // the dock put away and the window narrowed, the strip read at each
       break;
   }
   return G_SOURCE_REMOVE;
@@ -4758,6 +4845,7 @@ gboolean measures_probe_step(gpointer user) {
       std::fflush(stderr);
       measure_dialog_report(*a, "final");
       dock_measures_report(*a, "final");
+      strip_drive(*a, "measures");
       break;
     }
   }
diff --git a/src/ui_widgets.cpp b/src/ui_widgets.cpp
index 8bd5f54..7806a84 100644
--- a/src/ui_widgets.cpp
+++ b/src/ui_widgets.cpp
@@ -79,6 +79,8 @@ void install_css() {
       ".udpscope-badge { padding: 2px 12px; min-height: 0; border-radius: 14px; }\n"
       ".udpscope-badge-open { background-color: alpha(@accent_bg_color, 0.28); }\n"
       ".udpscope-badge-state { opacity: 0.7; }\n"
+      // The readouts strip's two text buttons: Adwaita's 34 px button would be taller than the strip.
+      "button.udpscope-strip-button { min-height: 0; padding: 1px 8px; }\n"
       // The contextual-help "(i)": a *mark*, not a button. Adwaita's menu button is a 34x34 control
       // (a 24 px floor plus 5 px of padding) with a 16 px glyph, which beside a heading reads as a
       // second toolbar button. Measured on libadwaita 1.10: the outer `menubutton` node *and* its