@@ -93,6 +93,7 @@ debug_icons = getenv("DEBUG_ICONS") != NULL;
     debug_fps = getenv("DEBUG_FPS") != NULL;
     debug_frames = getenv("DEBUG_FRAMES") != NULL;
     debug_dnd = getenv("DEBUG_DND") != NULL;
+    debug_thumbnails = getenv("DEBUG_THUMBNAILS") != NULL;
     if (debug_fps) {
         init_fps_distribution();
         char *s = getenv("TRACING_FPS_THRESHOLD");

@@ -58,6 +58,7 @@ char *panel_window_name = NULL;
 gboolean debug_geometry;
 gboolean debug_gradients;
 gboolean startup_notifications;
+gboolean debug_thumbnails;
 
 gboolean panel_autohide;
 int panel_autohide_show_timeout;

@@ -94,6 +94,7 @@ extern gboolean debug_geometry;
 extern gboolean debug_fps;
 extern double tracing_fps_threshold;
 extern gboolean debug_frames;
+extern gboolean debug_thumbnails;
 
 typedef struct Panel {
     Area area;

@@ -105,10 +105,6 @@ "Task %d %s",
              (int)win,
              task_template.title ? task_template.title : "null");
 
-    // fprintf(stderr, "tint2: %s %d: win = %ld, task = %s\n", __func__, __LINE__, win, task_template.title ?
-    // task_template.title : "??");
-    // fprintf(stderr, "tint2: new task %s win %u: desktop %d, monitor %d\n", new_task.title, win, new_task.desktop, monitor);
-
     GPtrArray *task_buttons = g_ptr_array_new();
     for (int j = 0; j < panels[monitor].num_desktops; j++) {
         if (task_template.desktop != ALL_DESKTOPS && task_template.desktop != j)
@@ -130,7 +126,6 @@ task_instance->win_w = task_template.win_w;
         task_instance->win_h = task_template.win_h;
         task_instance->current_state = TASK_UNDEFINED; // to update the current state later in set_task_state...
         if (task_instance->desktop == ALL_DESKTOPS && server.desktop != j) {
-            // fprintf(stderr, "tint2: %s %d: win = %ld hiding task: another desktop\n", __func__, __LINE__, win);
             task_instance->area.on_screen = always_show_all_desktop_tasks;
         }
         task_instance->title = task_template.title;
@@ -199,9 +194,6 @@ void remove_task(Task *task)
 {
     if (!task)
         return;
-
-    // fprintf(stderr, "tint2: %s %d: win = %ld, task = %s\n", __func__, __LINE__, task->win, task->title ? task->title :
-    // "??");
 
     if (taskbar_mode == MULTI_DESKTOP) {
         Panel *panel = task->area.panel;
@@ -212,7 +204,6 @@ Window win = task->win;
 
     // free title and icon just for the first task
     // even with task_on_all_desktop and with task_on_all_panel
-    // fprintf(stderr, "tint2: remove_task %s %d\n", task->title, task->desktop);
     if (task->title)
         free(task->title);
     if (task->thumbnail)
@@ -307,13 +298,6 @@ DATA32 icon_data[w * h];
                     for (int j = 0; j < w * h; ++j)
                         icon_data[j] = tmp_data[j];
                     img = imlib_create_image_using_copied_data(w, h, icon_data);
-                    if (0 && img)
-                        fprintf(stderr,
-                                "%s: Got %dx%d icon via _NET_WM_ICON for %s\n",
-                                __func__,
-                                w,
-                                h,
-                                task->title ? task->title : "task");
                 }
             }
             XFree(data);
@@ -333,13 +317,6 @@ 
                 XGetGeometry(server.display, hints->icon_pixmap, &root, &icon_x, &icon_y, &w, &h, &border_width, &bpp);
                 imlib_context_set_drawable(hints->icon_pixmap);
                 img = imlib_create_image_from_drawable(hints->icon_mask, 0, 0, w, h, 0);
-                if (0 && img)
-                    fprintf(stderr,
-                            "%s: Got %dx%d pixmap icon via WM_HINTS for %s\n",
-                            __func__,
-                            w,
-                            h,
-                            task->title ? task->title : "task");
             }
             XFree(hints);
         }
@@ -609,7 +586,6 @@ active_task = NULL;
     }
 
     Window w1 = get_active_window();
-    // fprintf(stderr, "tint2: Change active task %ld\n", w1);
 
     if (w1) {
         if (!get_task_buttons(w1)) {
@@ -630,7 +606,8 @@ return;
     double now = get_time();
     if (now - task->thumbnail_last_update < 0.1)
         return;
-    fprintf(stderr, "tint2: thumbnail for window: %s" RESET "\n", task->title ? task->title : "");
+    if (debug_thumbnails)
+        fprintf(stderr, "tint2: thumbnail for window: %s" RESET "\n", task->title ? task->title : "");
     cairo_surface_t *thumbnail = get_window_thumbnail(task->win, panel_config.g_task.thumbnail_width);
     if (!thumbnail)
         return;
@@ -638,7 +615,8 @@ if (task->thumbnail)
         cairo_surface_destroy(task->thumbnail);
     task->thumbnail = thumbnail;
     task->thumbnail_last_update = get_time();
-    fprintf(stderr, YELLOW "tint2: %s took %f ms (window: %s)" RESET "\n", __func__, 1000 * (task->thumbnail_last_update - now), task->title ? task->title : "");
+    if (debug_thumbnails)
+        fprintf(stderr, YELLOW "tint2: %s took %f ms (window: %s)" RESET "\n", __func__, 1000 * (task->thumbnail_last_update - now), task->title ? task->title : "");
     if (g_tooltip.mapped && (g_tooltip.area == &task->area)) {
         tooltip_update_contents_for(&task->area);
         tooltip_update();
@@ -833,7 +811,6 @@ }
 
 void task_update_desktop(Task *task)
 {
-    // fprintf(stderr, "tint2: %s %d:\n", __func__, __LINE__);
     Window win = task->win;
     remove_task(task);
     task = add_task(win);

@@ -376,7 +376,8 @@ void taskbar_start_thumbnail_timer(ThumbnailUpdateMode mode)
 {
     if (!panel_config.g_task.thumbnail_enabled)
         return;
-    fprintf(stderr, BLUE "tint2: taskbar_start_thumbnail_timer %s" RESET "\n", mode == THUMB_MODE_ACTIVE_WINDOW ? "active" : mode == THUMB_MODE_TOOLTIP_WINDOW ? "tooltip" : "all");
+    if (debug_thumbnails)
+        fprintf(stderr, BLUE "tint2: taskbar_start_thumbnail_timer %s" RESET "\n", mode == THUMB_MODE_ACTIVE_WINDOW ? "active" : mode == THUMB_MODE_TOOLTIP_WINDOW ? "tooltip" : "all");
     change_timeout(mode == THUMB_MODE_ALL ? &thumbnail_update_timer_all :
                                             mode == THUMB_MODE_ACTIVE_WINDOW ? &thumbnail_update_timer_active : &thumbnail_update_timer_tooltip,
                    mode == THUMB_MODE_TOOLTIP_WINDOW ? 1000 : 500,
@@ -497,7 +498,6 @@ void taskbar_refresh_tasklist()
 {
     if (!taskbar_enabled)
         return;
-    // fprintf(stderr, "tint2: %s %d:\n", __func__, __LINE__);
 
     int num_results;
     Window *win = server_get_property(server.root_win, server.atom._NET_CLIENT_LIST, XA_WINDOW, &num_results);
@@ -551,7 +551,6 @@ {
     Taskbar *taskbar = (Taskbar *)obj;
     Panel *panel = (Panel *)taskbar->area.panel;
 
-    // fprintf(stderr, "tint2: resize_taskbar %d %d\n", taskbar->area.posx, taskbar->area.posy);
     if (panel_horizontal) {
         relayout_with_constraint(&taskbar->area, panel->g_task.maximum_width);
 
@@ -815,7 +814,8 @@ {
     if (!panel_config.g_task.thumbnail_enabled)
         return;
     ThumbnailUpdateMode mode = (ThumbnailUpdateMode)(long)arg;
-    fprintf(stderr, BLUE "tint2: taskbar_update_thumbnails %s" RESET "\n", mode == THUMB_MODE_ACTIVE_WINDOW ? "active" : mode == THUMB_MODE_TOOLTIP_WINDOW ? "tooltip" : "all");
+    if (debug_thumbnails)
+        fprintf(stderr, BLUE "tint2: taskbar_update_thumbnails %s" RESET "\n", mode == THUMB_MODE_ACTIVE_WINDOW ? "active" : mode == THUMB_MODE_TOOLTIP_WINDOW ? "tooltip" : "all");
     double start_time = get_time();
     for (int i = 0; i < num_panels; i++) {
         Panel *panel = &panels[i];

@@ -637,10 +637,12 @@ if (image_surface && cairo_surface_is_blank(image_surface)) {
             cairo_surface_destroy(image_surface);
             image_surface = NULL;
         }
-        if (!image_surface)
-            fprintf(stderr, YELLOW "tint2: XShmGetImage failed, trying slower method" RESET "\n");
-        else
-            fprintf(stderr, "tint2: captured window using XShmGetImage\n");
+        if (debug_thumbnails) {
+            if (!image_surface)
+                fprintf(stderr, YELLOW "tint2: XShmGetImage failed, trying slower method" RESET "\n");
+            else
+                fprintf(stderr, "tint2: captured window using XShmGetImage\n");
+        }
     }
 
     if (!image_surface) {
@@ -649,10 +651,12 @@ if (image_surface && cairo_surface_is_blank(image_surface)) {
             cairo_surface_destroy(image_surface);
             image_surface = NULL;
         }
-        if (!image_surface)
-            fprintf(stderr, YELLOW "tint2: XGetImage failed, trying slower method" RESET "\n");
-        else
-            fprintf(stderr, "tint2: captured window using XGetImage\n");
+        if (debug_thumbnails) {
+            if (!image_surface)
+                fprintf(stderr, YELLOW "tint2: XGetImage failed, trying slower method" RESET "\n");
+            else
+                fprintf(stderr, "tint2: captured window using XGetImage\n");
+        }
     }
 
     if (!image_surface) {
@@ -661,10 +665,12 @@ if (image_surface && cairo_surface_is_blank(image_surface)) {
             cairo_surface_destroy(image_surface);
             image_surface = NULL;
         }
-        if (!image_surface)
-            fprintf(stderr, YELLOW "tint2: capturing window failed" RESET "\n");
-        else
-            fprintf(stderr, "tint2: captured window using cairo\n");
+        if (debug_thumbnails) {
+            if (!image_surface)
+                fprintf(stderr, YELLOW "tint2: capturing window failed" RESET "\n");
+            else
+                fprintf(stderr, "tint2: captured window using cairo\n");
+        }
     }
 
     if (!image_surface)