Move the displayed 'fields' details view with the cursor line

src/field_overlay_source.cc

@@ -546,7 +546,7 @@ field_overlay_source::list_value_for_overlay(const listview_curses& lv,
                                              vis_line_t row,
                                              attr_line_t& value_out)
 {
-    if (y == 0) {
+    if (y <= 0) {
         this->build_field_lines(lv);
         return false;
     }

src/listview_curses.cc

@@ -217,13 +217,14 @@ listview_curses::do_update()
         std::vector<attr_line_t> rows(
             std::min((size_t) height, row_count - (int) this->lv_top));
         this->lv_source->listview_value_for_rows(*this, row, rows);
+        vis_line_t selected_in_view = this->get_selection() - this->get_top();
         while (y < bottom) {
             lr.lr_start = this->lv_left;
             lr.lr_end = this->lv_left + wrap_width;
             if (this->lv_overlay_source != nullptr
                 && this->lv_overlay_source->list_value_for_overlay(
                     *this,
-                    y - this->lv_y,
+                    y - selected_in_view - this->lv_y,
                     bottom - this->lv_y,
                     row,
                     overlay_line))

src/listview_curses.hh

@@ -552,7 +552,8 @@ protected:
     bool lv_word_wrap{false};
     bool lv_selectable{true};
     vis_line_t lv_selection{0};
-    vis_line_t lv_displayed_rows{0};
+    vis_line_t lv_displayed_rows{0}; /*< Number of actually displayed rows,
+                                        excluding wrapped and empty lines. */
 
     struct timeval lv_mouse_time {
         0, 0