diff --git a/lv_conf_template.h b/lv_conf_template.h
index 30df1144c2..090ca6889c 100644
--- a/lv_conf_template.h
+++ b/lv_conf_template.h
@@ -351,6 +351,7 @@ typedef void * lv_indev_drv_user_data_t;            /*Type of user data in the i
 /* Demonstrate special features */
 #define LV_FONT_MONTSERRAT_12_SUBPX      0
 #define LV_FONT_MONTSERRAT_28_COMPRESSED 0  /*bpp = 3*/
+#define LV_FONT_SIMSUN_16_CJK            0  /*1000 most common CJK radicals*/
 
 /*Pixel perfect monospace font
  * http://pelulamu.net/unscii/ */
diff --git a/src/lv_conf_internal.h b/src/lv_conf_internal.h
index ba77fc14f2..35d290937d 100644
--- a/src/lv_conf_internal.h
+++ b/src/lv_conf_internal.h
@@ -525,6 +525,9 @@
 #ifndef LV_FONT_MONTSERRAT_28_COMPRESSED
 #define LV_FONT_MONTSERRAT_28_COMPRESSED 0  /*bpp = 3*/
 #endif
+#ifndef LV_FONT_SIMSUN_16_CJK
+#define LV_FONT_SIMSUN_16_CJK            0  /*1000 most common CJK radicals*/
+#endif
 
 /*Pixel perfect monospace font
  * http://pelulamu.net/unscii/ */
diff --git a/src/lv_core/lv_group.h b/src/lv_core/lv_group.h
index aa32b503a1..f5fb9e4fbc 100644
--- a/src/lv_core/lv_group.h
+++ b/src/lv_core/lv_group.h
@@ -147,20 +147,6 @@ void lv_group_focus_freeze(lv_group_t * group, bool en);
  */
 lv_res_t lv_group_send_data(lv_group_t * group, uint32_t c);
 
-/**
- * Set a function for a group which will modify the object's style if it is in focus
- * @param group pointer to a group
- * @param style_mod_cb the style modifier function pointer
- */
-void lv_group_set_style_mod_cb(lv_group_t * group, lv_group_style_mod_cb_t style_mod_cb);
-
-/**
- * Set a function for a group which will modify the object's style if it is in focus in edit mode
- * @param group pointer to a group
- * @param style_mod_edit_cb the style modifier function pointer
- */
-void lv_group_set_style_mod_edit_cb(lv_group_t * group, lv_group_style_mod_cb_t style_mod_edit_cb);
-
 /**
  * Set a function for a group which will be called when a new object is focused
  * @param group pointer to a group
@@ -222,20 +208,6 @@ lv_group_user_data_t * lv_group_get_user_data(lv_group_t * group);
 
 #endif
 
-/**
- * Get a the style modifier function of a group
- * @param group pointer to a group
- * @return pointer to the style modifier function
- */
-lv_group_style_mod_cb_t lv_group_get_style_mod_cb(const lv_group_t * group);
-
-/**
- * Get a the style modifier function of a group in edit mode
- * @param group pointer to a group
- * @return pointer to the style modifier function
- */
-lv_group_style_mod_cb_t lv_group_get_style_mod_edit_cb(const lv_group_t * group);
-
 /**
  * Get the focus callback function of a group
  * @param group pointer to a group
diff --git a/src/lv_core/lv_obj.h b/src/lv_core/lv_obj.h
index 5dcb62b02a..905a38d77b 100644
--- a/src/lv_core/lv_obj.h
+++ b/src/lv_core/lv_obj.h
@@ -1197,20 +1197,6 @@ bool lv_obj_get_gesture_parent(const lv_obj_t * obj);
 
 lv_bidi_dir_t lv_obj_get_base_dir(const lv_obj_t * obj);
 
-/**
- * Get the opa scale enable parameter
- * @param obj pointer to an object
- * @return true: opa scaling is enabled for this object and all children; false: no opa scaling
- */
-lv_opa_t lv_obj_get_opa_scale_enable(const lv_obj_t * obj);
-
-/**
- * Get the opa scale parameter of an object
- * @param obj pointer to an object
- * @return opa scale [0..255]
- */
-lv_opa_t lv_obj_get_opa_scale(const lv_obj_t * obj);
-
 /**
  * Get the protect field of an object
  * @param obj pointer to an object
diff --git a/src/lv_draw/lv_draw_blend.c b/src/lv_draw/lv_draw_blend.c
index 6757034f29..9961e182b6 100644
--- a/src/lv_draw/lv_draw_blend.c
+++ b/src/lv_draw/lv_draw_blend.c
@@ -119,6 +119,8 @@ void lv_blend_fill(const lv_area_t * clip_area, const lv_area_t * fill_area,
                    lv_color_t color, lv_opa_t * mask, lv_draw_mask_res_t mask_res, lv_opa_t opa,
                    lv_blend_mode_t mode)
 {
+    static int asd = 0;
+    asd++;
     /*Do not draw transparent things*/
     if(opa < LV_OPA_MIN) return;
     if(mask_res == LV_DRAW_MASK_RES_FULL_TRANSP) return;
diff --git a/src/lv_themes/lv_theme.h b/src/lv_themes/lv_theme.h
index 9470540f15..0984c026ca 100644
--- a/src/lv_themes/lv_theme.h
+++ b/src/lv_themes/lv_theme.h
@@ -171,7 +171,6 @@ void lv_theme_set_act(lv_theme_t * th);
  */
 lv_theme_t * lv_theme_get_act(void);
 
-lv_style_t * lv_theme_get_style(lv_theme_style_t name);
 
 void lv_theme_apply(lv_obj_t * obj, lv_theme_style_t name);
 
diff --git a/src/lv_widgets/lv_btnmatrix.h b/src/lv_widgets/lv_btnmatrix.h
index 3b01d8e326..04effd2ff2 100644
--- a/src/lv_widgets/lv_btnmatrix.h
+++ b/src/lv_widgets/lv_btnmatrix.h
@@ -114,14 +114,6 @@ void lv_btnmatrix_set_ctrl_map(lv_obj_t * btnm, const lv_btnmatrix_ctrl_t ctrl_m
  */
 void lv_btnmatrix_set_focused_btn(lv_obj_t * btnm, uint16_t id);
 
-/**
- * Set a style of a button matrix
- * @param btnm pointer to a button matrix object
- * @param type which style should be set
- * @param style pointer to a style
- */
-void lv_btnmatrix_set_style(lv_obj_t * btnm, lv_btnmatrix_part_t type, const lv_style_t * style);
-
 /**
  * Enable recoloring of button's texts
  * @param btnm pointer to button matrix object
diff --git a/src/lv_widgets/lv_chart.c b/src/lv_widgets/lv_chart.c
index 924e2e3943..773e6eca93 100644
--- a/src/lv_widgets/lv_chart.c
+++ b/src/lv_widgets/lv_chart.c
@@ -983,71 +983,6 @@ static void draw_series_column(lv_obj_t * chart, const lv_area_t * series_area,
     }
 }
 
-///**
-// * Draw the data lines as vertical lines on a chart if there is only 1px between point
-// * @param obj pointer to chart object
-// */
-//static void lv_chart_draw_vertical_lines(lv_obj_t * chart, const lv_area_t * mask)
-//{
-//
-//    lv_chart_ext_t * ext = lv_obj_get_ext_attr(chart);
-//    lv_coord_t w         = lv_obj_get_width(chart);
-//    /*Vertical lines works only if the width == point count. Else use the normal line type*/
-//    if(ext->point_cnt != w) {
-//        lv_chart_draw_lines(chart, mask);
-//        return;
-//    }
-//
-//    uint16_t i;
-//    lv_point_t p1;
-//    lv_point_t p2;
-//    lv_coord_t p_act;
-//    lv_coord_t h     = lv_obj_get_height(chart);
-//    lv_coord_t x_ofs = chart->coords.x1;
-//    lv_coord_t y_ofs = chart->coords.y1;
-//    int32_t y_tmp;
-//    lv_chart_series_t * ser;
-//    lv_opa_t opa_scale = lv_obj_get_opa_scale(chart);
-//    lv_style_t style;
-//    lv_style_copy(&style, &lv_style_plain);
-//    style.line.opa   = ext->series.opa;
-//    style.line.width = ext->series.width;
-//
-//    /*Go through all data lines*/
-//    LV_LL_READ_BACK(ext->series_ll, ser)
-//    {
-//        lv_coord_t start_point = ext->update_mode == LV_CHART_UPDATE_MODE_SHIFT ? ser->start_point : 0;
-//        style.line.color       = ser->color;
-//
-//        p1.x  = 0 + x_ofs;
-//        p2.x  = 0 + x_ofs;
-//        y_tmp = (int32_t)((int32_t)ser->points[0] - ext->ymin) * h;
-//        y_tmp = y_tmp / (ext->ymax - ext->ymin);
-//        p2.y  = h - y_tmp + y_ofs;
-//        p1.y  = p2.y;
-//
-//        for(i = 0; i < ext->point_cnt; i++) {
-//            p_act = (start_point + i) % ext->point_cnt;
-//
-//            y_tmp = (int32_t)((int32_t)ser->points[p_act] - ext->ymin) * h;
-//            y_tmp = y_tmp / (ext->ymax - ext->ymin);
-//            p2.y  = h - y_tmp + y_ofs;
-//
-//            if(p1.y == p2.y) {
-//                p2.x++;
-//            }
-//
-//            if(ser->points[p_act] != LV_CHART_POINT_DEF) {
-//                lv_draw_line(&p1, &p2, mask, &style, opa_scale);
-//            }
-//
-//            p2.x = ((w * p_act) / (ext->point_cnt - 1)) + x_ofs;
-//            p1.x = p2.x;
-//            p1.y = p2.y;
-//        }
-//    }
-//}
-
 /**
  * Create iterator for newline-separated list
  * @param list pointer to newline-separated labels list
diff --git a/src/lv_widgets/lv_checkbox.h b/src/lv_widgets/lv_checkbox.h
index 9587f8e32e..7a15366920 100644
--- a/src/lv_widgets/lv_checkbox.h
+++ b/src/lv_widgets/lv_checkbox.h
@@ -106,14 +106,6 @@ static inline void lv_checkbox_set_disabled(lv_obj_t * cb)
     lv_btn_set_state(cb, LV_BTN_STATE_DISABLED);
 }
 
-/**
- * Set a style of a check box
- * @param cb pointer to check box object
- * @param type which style should be set
- * @param style pointer to a style
- *  */
-void lv_checkbox_set_style(lv_obj_t * cb, lv_checkbox_style_t type, const lv_style_t * style);
-
 /*=====================
  * Getter functions
  *====================*/
diff --git a/src/lv_widgets/lv_cpicker.h b/src/lv_widgets/lv_cpicker.h
index d2d5e29877..2aef0d732e 100644
--- a/src/lv_widgets/lv_cpicker.h
+++ b/src/lv_widgets/lv_cpicker.h
@@ -212,13 +212,6 @@ lv_color_t lv_cpicker_get_color(lv_obj_t * cpicker);
  */
 bool lv_cpicker_get_knob_colored(lv_obj_t * cpicker);
 
-/**
- *  Whether the preview is enabled or not
- * @param cpicker pointer to colorpicker object
- * @return en true: preview is enabled; false: preview is disabled
- */
-bool lv_cpicker_get_preview(lv_obj_t * cpicker);
-
 /*=====================
  * Other functions
  *====================*/
diff --git a/src/lv_widgets/lv_msgbox.h b/src/lv_widgets/lv_msgbox.h
index e7e261d170..84c4c1e0a3 100644
--- a/src/lv_widgets/lv_msgbox.h
+++ b/src/lv_widgets/lv_msgbox.h
@@ -119,14 +119,6 @@ void lv_msgbox_start_auto_close(lv_obj_t * mbox, uint16_t delay);
  */
 void lv_msgbox_stop_auto_close(lv_obj_t * mbox);
 
-/**
- * Set a style of a message box
- * @param mbox pointer to a message box object
- * @param type which style should be set
- * @param style pointer to a style
- */
-void lv_msgbox_set_style(lv_obj_t * mbox, lv_msgbox_style_t type, const lv_style_t * style);
-
 /**
  * Set whether recoloring is enabled. Must be called after `lv_msgbox_add_btns`.
  * @param btnm pointer to button matrix object
diff --git a/src/lv_widgets/lv_spinner.h b/src/lv_widgets/lv_spinner.h
index 5ee51f1ee4..e9127d94a7 100644
--- a/src/lv_widgets/lv_spinner.h
+++ b/src/lv_widgets/lv_spinner.h
@@ -112,14 +112,6 @@ void lv_spinner_set_spin_time(lv_obj_t * preload, uint16_t time);
  * Setter functions
  *====================*/
 
-/**
- * Set a style of a pre loader.
- * @param preload pointer to pre loader object
- * @param type which style should be set
- * @param style pointer to a style
- *  */
-void lv_spinner_set_style(lv_obj_t * preload, lv_spinner_style_t type, const lv_style_t * style);
-
 /**
  * Set the animation type of a spinner.
  * @param preload pointer to pre loader object
@@ -150,14 +142,6 @@ lv_anim_value_t lv_spinner_get_arc_length(const lv_obj_t * preload);
  */
 uint16_t lv_spinner_get_spin_time(const lv_obj_t * preload);
 
-/**
- * Get style of a pre loader.
- * @param preload pointer to pre loader object
- * @param type which style should be get
- * @return style pointer to the style
- *  */
-const lv_style_t * lv_spinner_get_style(const lv_obj_t * preload, lv_spinner_style_t type);
-
 /**
  * Get the animation type of a spinner.
  * @param preload pointer to pre loader object
diff --git a/src/lv_widgets/lv_switch.h b/src/lv_widgets/lv_switch.h
index 35b7b0abbf..609e44fcc9 100644
--- a/src/lv_widgets/lv_switch.h
+++ b/src/lv_widgets/lv_switch.h
@@ -90,22 +90,6 @@ void lv_switch_off(lv_obj_t * sw, lv_anim_enable_t anim);
  */
 bool lv_switch_toggle(lv_obj_t * sw, lv_anim_enable_t anim);
 
-/**
- * Set an image to display on the knob of the switch.
- * @param sw pointer to a switch object
- * @param img_src pointer to an `lv_img_dsc_t` variable or a path to an image
- *        (not an `lv_img` object)
- */
-void lv_switch_set_knob_img(lv_obj_t * sw, const void * img_src);
-
-/**
- * Set an image to display on the knob of the switch when it's in ON state
- * @param sw pointer to a switch object
- * @param img_src pointer to an `lv_img_dsc_t` variable or a path to an image
- *        (not an `lv_img` object)
- */
-void lv_switch_set_knob_on_img(lv_obj_t * sw, const void * img_src);
-
 /**
  * Set the animation time of the switch
  * @param sw pointer to a  switch object
@@ -131,21 +115,7 @@ static inline bool lv_switch_get_state(const lv_obj_t * sw)
     lv_switch_ext_t * ext = (lv_switch_ext_t *)lv_obj_get_ext_attr(sw);
     return ext->state ? true : false;
 }
-/**
- * Get an image to display on the knob of the switch when it's in OFF state
- * @param sw pointer to a switch object
- * @return the image source: pointer to an `lv_img_dsc_t` variable or a path to an image
- *         (not an `lv_img` object)
- */
-const void * lv_slider_get_knob_off_img(lv_obj_t * sw, const void * img_src);
 
-/**
- * Get an image to display on the knob of the switch when it's in ON state
- * @param sw pointer to a switch object
- * @return the image source: pointer to an `lv_img_dsc_t` variable or a path to an image
- *         (not an `lv_img` object)
- */
-const void * lv_slider_get_knob_on_img(lv_obj_t * sw, const void * img_src);
 /**
  * Get the animation time of the switch
  * @param sw pointer to a  switch object
diff --git a/src/lv_widgets/lv_win.h b/src/lv_widgets/lv_win.h
index ebb9e3d647..af4ae16e11 100644
--- a/src/lv_widgets/lv_win.h
+++ b/src/lv_widgets/lv_win.h
@@ -185,13 +185,6 @@ const char * lv_win_get_title(const lv_obj_t * win);
  */
 lv_obj_t * lv_win_get_content(const lv_obj_t * win);
 
-/**
- * Get the control button size of a window
- * @param win pointer to a window object
- * @return control button size
- */
-lv_coord_t lv_win_get_btn_size(const lv_obj_t * win);
-
 /**
  * Get the header height
  * @param win pointer to a window object