diff --git a/radio/src/gui/colorlcd/draw_functions.cpp b/radio/src/gui/colorlcd/draw_functions.cpp
index b5c2ac1a1..7dd4b0491 100644
--- a/radio/src/gui/colorlcd/draw_functions.cpp
+++ b/radio/src/gui/colorlcd/draw_functions.cpp
@@ -234,7 +234,7 @@ void drawCurveRef(BitmapBuffer * dc, coord_t x, coord_t y, const CurveRef & curv
         break;
 
       case CURVE_REF_FUNC:
-        dc->drawTextAtIndex(x, y, STR_VCURVEFUNC, curve.value, flags);
+        dc->drawText(x, y, STR_VCURVEFUNC[curve.value], flags);
         break;
 
       case CURVE_REF_CUSTOM:
diff --git a/radio/src/lua/api_colorlcd.cpp b/radio/src/lua/api_colorlcd.cpp
index 9993e76c4..9d47fbbea 100644
--- a/radio/src/lua/api_colorlcd.cpp
+++ b/radio/src/lua/api_colorlcd.cpp
@@ -408,7 +408,7 @@ static int luaLcdDrawNumber(lua_State *L)
   char s[49];
   int val = luaL_checkinteger(L, 3);
   LcdFlags flags = luaL_optunsigned(L, 4, 0);
-  BitmapBuffer::formatNumberAsString(s, 49, val, flags & 0xFFFF);
+  formatNumberAsString(s, 49, val, flags & 0xFFFF);
   drawString(L, s, flags);
   return 0;
 }
diff --git a/radio/src/strhelpers.cpp b/radio/src/strhelpers.cpp
index cfe371eaf..7c964444c 100644
--- a/radio/src/strhelpers.cpp
+++ b/radio/src/strhelpers.cpp
@@ -407,7 +407,7 @@ char *getValueOrGVarString(char *dest, size_t len, gvar_t value, gvar_t vmin, gv
   }
 
   value += offset;
-  BitmapBuffer::formatNumberAsString(dest, len, value, flags, 0, nullptr, suffix);
+  formatNumberAsString(dest, len, value, flags, 0, nullptr, suffix);
   return dest;
 }
 #endif
@@ -808,9 +808,9 @@ char *getValueWithUnit(char *dest, size_t len, int32_t val, uint8_t unit,
   if (unit == UNIT_CELLS) unit = UNIT_VOLTS;
   if ((flags & NO_UNIT) || (unit == UNIT_RAW)) {
     flags = flags & (~NO_UNIT);
-    BitmapBuffer::formatNumberAsString(dest, len, val, flags);
+    formatNumberAsString(dest, len, val, flags);
   } else {
-    BitmapBuffer::formatNumberAsString(dest, len, val, flags, 0, nullptr,
+    formatNumberAsString(dest, len, val, flags, 0, nullptr,
                                        STR_VTELEMUNIT[unit]);
   }
 
@@ -861,7 +861,7 @@ char *getSourceCustomValueString(char (&dest)[L], source_t source, int32_t val,
     return getTimerString(dest, val, timerOptions);
   }
   else if (source == MIXSRC_TX_VOLTAGE) {
-    BitmapBuffer::formatNumberAsString(dest, len, val, flags | PREC1);
+    formatNumberAsString(dest, len, val, flags | PREC1);
     return dest;
   }
 #if defined(INTERNAL_GPS)
@@ -884,34 +884,75 @@ char *getSourceCustomValueString(char (&dest)[L], source_t source, int32_t val,
 #endif
 #if defined(LUA_INPUTS)
   else if (source >= MIXSRC_FIRST_LUA && source <= MIXSRC_LAST_LUA) {
-    BitmapBuffer::formatNumberAsString(dest, len, val, flags);
+    formatNumberAsString(dest, len, val, flags);
   }
 #endif
   else if (source < MIXSRC_FIRST_CH) {
     val = calcRESXto100(val);
-    BitmapBuffer::formatNumberAsString(dest, len, val, flags);
+    formatNumberAsString(dest, len, val, flags);
   }
   else if (source <= MIXSRC_LAST_CH) {
     if (g_eeGeneral.ppmunit == PPM_PERCENT_PREC1) {
       val = calcRESXto1000(val);
-      BitmapBuffer::formatNumberAsString(dest, len, val, flags | PREC1);
+      formatNumberAsString(dest, len, val, flags | PREC1);
     } else {
       val = calcRESXto100(val);
-      BitmapBuffer::formatNumberAsString(dest, len, val, flags);
+      formatNumberAsString(dest, len, val, flags);
     }
   }
   else {
-    BitmapBuffer::formatNumberAsString(dest, len, val, flags);
+    formatNumberAsString(dest, len, val, flags);
   }
 
   return dest;
 }
 
+void formatNumberAsString(char *buffer, uint8_t buffer_size, int32_t val, LcdFlags flags, uint8_t len, const char * prefix, const char * suffix)
+{
+  if (buffer) {
+    char str[48+1]; // max=16 for the prefix, 16 chars for the number, 16 chars for the suffix
+    char *s = str + 32;
+    *s = '\0';
+    int idx = 0;
+    int mode = MODE(flags);
+    bool neg = false;
+    if (val < 0) {
+      val = -val;
+      neg = true;
+    }
+    do {
+      *--s = '0' + (val % 10);
+      ++idx;
+      val /= 10;
+      if (mode != 0 && idx == mode) {
+        mode = 0;
+        *--s = '.';
+        if (val == 0)
+          *--s = '0';
+      }
+    } while (val != 0 || mode > 0 || (mode == MODE(LEADING0) && idx < len));
+    if (neg) *--s = '-';
+
+    // TODO needs check on all string lengths ...
+    if (prefix) {
+      int len = strlen(prefix);
+      if (len <= 16) {
+        s -= len;
+        strncpy(s, prefix, len);
+      }
+    }
+    if (suffix) {
+      strncpy(&str[32], suffix, 16);
+    }
+    strncpy(buffer, s, buffer_size);
+  }
+}
+
 std::string formatNumberAsString(int32_t val, LcdFlags flags, uint8_t len,
                                  const char *prefix, const char *suffix)
 {
   char s[49];
-  BitmapBuffer::formatNumberAsString(s, 49, val, flags, len, prefix, suffix);
+  formatNumberAsString(s, 49, val, flags, len, prefix, suffix);
   return std::string(s);
 }
 
diff --git a/radio/src/strhelpers.h b/radio/src/strhelpers.h
index 161da6e5d..a1b2f4119 100644
--- a/radio/src/strhelpers.h
+++ b/radio/src/strhelpers.h
@@ -80,6 +80,7 @@ char *strSetCursor(char *dest, int position);
 char *strAppendDate(char *str, bool time = false);
 char *strAppendFilename(char *dest, const char *filename, const int size);
 std::string formatNumberAsString(int32_t val, LcdFlags flags = 0, uint8_t len = 0, const char * prefix = nullptr, const char * suffix = nullptr);
+void formatNumberAsString(char *buffer, const uint8_t buffer_size, int32_t val, LcdFlags flags = 0, uint8_t len = 0, const char * prefix = nullptr, const char * suffix = nullptr);
 
 #if !defined(BOOT)
 char *getStringAtIndex(char *dest, const char *const *s, int idx);
diff --git a/radio/src/thirdparty/libopenui/src/bitmapbuffer.cpp b/radio/src/thirdparty/libopenui/src/bitmapbuffer.cpp
index fbf9133ca..06838b6da 100644
--- a/radio/src/thirdparty/libopenui/src/bitmapbuffer.cpp
+++ b/radio/src/thirdparty/libopenui/src/bitmapbuffer.cpp
@@ -17,7 +17,6 @@
  */
 
 #include <math.h>
-#include <string.h>
 
 #include "board.h"
 #include "bitmapbuffer.h"
@@ -25,6 +24,7 @@
 #include "libopenui_file.h"
 #include "font.h"
 #include "dma2d.h"
+#include "strhelpers.h"
 
 #include "lvgl/src/draw/sw/lv_draw_sw.h"
 
@@ -990,55 +990,6 @@ void BitmapBuffer::drawMask(coord_t x, coord_t y, const BitmapBuffer * mask, Lcd
   }
 }
 
-void BitmapBuffer::drawMask(coord_t x, coord_t y, const BitmapBuffer * mask, const BitmapBuffer * srcBitmap, coord_t offsetX, coord_t offsetY, coord_t width, coord_t height)
-{
-  if (!mask || !srcBitmap)
-    return;
-
-  APPLY_OFFSET();
-
-  coord_t maskWidth = mask->width();
-  coord_t maskHeight = mask->height();
-
-  if (!width || width > maskWidth) {
-    width = maskWidth;
-  }
-
-  if (!height || height > maskHeight) {
-    height = maskHeight;
-  }
-
-  if (x + width > xmax) {
-    width = xmax - x;
-  }
-
-  if (x < xmin) {
-    width += x - xmin;
-    offsetX -= x - xmin;
-    x = xmin;
-  }
-
-  if (y >= ymax || x >= xmax || width <= 0 || x + width < xmin || y + height < ymin)
-    return;
-
-
-  // TODO: This should be doable the same way as with
-  //       drawBitmapPattern() (just with ARGB as input).
-  //
-  DMAWait();
-  for (coord_t row = 0; row < height; row++) {
-    if (y + row < ymin || y + row >= ymax)
-      continue;
-    pixel_t * p = getPixelPtrAbs(x, y + row);
-    const pixel_t * q = mask->getPixelPtrAbs(offsetX, offsetY + row);
-    for (coord_t col = 0; col < width; col++) {
-      drawAlphaPixel(p, *((uint8_t *)q), *srcBitmap->getPixelPtrAbs(row, col));
-      MOVE_TO_NEXT_RIGHT_PIXEL(p);
-      MOVE_TO_NEXT_RIGHT_PIXEL(q);
-    }
-  }
-}
-
 // Apply a mask ('bmp') + color ('flags') on top of current pixels:
 //
 //  drawAlphaPixel(bmp[x][y], pixel(x,y), color)
@@ -1161,49 +1112,6 @@ coord_t BitmapBuffer::drawSizedText(coord_t x, coord_t y, const char *s,
   return ((flags & RIGHT) ? orig_pos : pos) - offsetX;
 }
 
-void BitmapBuffer::formatNumberAsString(char *buffer, uint8_t buffer_size, int32_t val, LcdFlags flags, uint8_t len, const char * prefix, const char * suffix)
-{
-  if (buffer == nullptr) {
-    return;
-  }
-
-  char str[48+1]; // max=16 for the prefix, 16 chars for the number, 16 chars for the suffix
-  char *s = str + 32;
-  *s = '\0';
-  int idx = 0;
-  int mode = MODE(flags);
-  bool neg = false;
-  if (val < 0) {
-    val = -val;
-    neg = true;
-  }
-  do {
-    *--s = '0' + (val % 10);
-    ++idx;
-    val /= 10;
-    if (mode != 0 && idx == mode) {
-      mode = 0;
-      *--s = '.';
-      if (val == 0)
-        *--s = '0';
-    }
-  } while (val != 0 || mode > 0 || (mode == MODE(LEADING0) && idx < len));
-  if (neg) *--s = '-';
-
-  // TODO needs check on all string lengths ...
-  if (prefix) {
-    int len = strlen(prefix);
-    if (len <= 16) {
-      s -= len;
-      strncpy(s, prefix, len);
-    }
-  }
-  if (suffix) {
-    strncpy(&str[32], suffix, 16);
-  }
-  strncpy(buffer, s, buffer_size);
-}
-
 coord_t BitmapBuffer::drawNumber(coord_t x, coord_t y, int32_t val, LcdFlags flags, uint8_t len, const char * prefix, const char * suffix)
 {
   char s[49];
@@ -1219,39 +1127,6 @@ void drawSolidRect(BitmapBuffer * dc, coord_t x, coord_t y, coord_t w, coord_t h
   dc->drawSolidFilledRect(x, y+h-thickness, w, thickness, flags);
 }
 
-//void BitmapBuffer::drawBitmapPie(int x0, int y0, const uint16_t * img, int startAngle, int endAngle)
-//{
-//  const uint16_t * q = img;
-//  coord_t width = *q++;
-//  coord_t height = *q++;
-//
-//  int slopes[4];
-//  if (!evalSlopes(slopes, startAngle, endAngle))
-//    return;
-//
-//  int w2 = width/2;
-//  int h2 = height/2;
-//
-//  for (int y=h2-1; y>=0; y--) {
-//    for (int x=w2-1; x>=0; x--) {
-//      int slope = (x==0 ? 99000 : y*100/x);
-//      if (slope >= slopes[0] && slope < slopes[1]) {
-//        *getPixelPtr(x0+w2+x, y0+h2-y) = q[(h2-y)*width + w2+x];
-//      }
-//      if (-slope >= slopes[0] && -slope < slopes[1]) {
-//        *getPixelPtr(x0+w2+x, y0+h2+y) = q[(h2+y)*width + w2+x];
-//      }
-//      if (slope >= slopes[2] && slope < slopes[3]) {
-//        *getPixelPtr(x0+w2-x, y0+h2-y) = q[(h2-y)*width + w2-x];
-//      }
-//      if (-slope >= slopes[2] && -slope < slopes[3]) {
-//        *getPixelPtr(x0+w2-x, y0+h2+y)  = q[(h2+y)*width + w2-x];
-//      }
-//    }
-//  }
-//}
-//
-
 BitmapBuffer * BitmapBuffer::loadBitmap(const char * filename, BitmapFormats fmt)
 {
   //TRACE("  BitmapBuffer::loadBitmap(%s)", filename);
@@ -1262,11 +1137,6 @@ BitmapBuffer * BitmapBuffer::loadBitmap(const char * filename, BitmapFormats fmt
     return load_stb(filename, fmt);
 }
 
-BitmapBuffer * BitmapBuffer::loadRamBitmap(const uint8_t * buffer, int len)
-{
-  return load_stb_buffer(buffer, len);
-}
-
 BitmapBuffer * BitmapBuffer::loadMask(const char * filename)
 {
   BitmapBuffer * bitmap = BitmapBuffer::loadBitmap(filename);
@@ -1324,77 +1194,6 @@ BitmapBuffer* BitmapBuffer::load8bitMaskLZ4(const uint8_t* compressed_data)
   return bitmap;
 }
 
-BitmapBuffer * BitmapBuffer::invertMask() const
-{
-  BitmapBuffer * result = new BitmapBuffer(format, width(), height());
-  pixel_t * srcData = data;
-  pixel_t * destData = result->data;
-  for (auto y = 0; y < height(); y++) {
-    for (auto x = 0; x < width(); x++) {
-      destData[x] = OPACITY_MAX - (uint8_t)srcData[x];
-    }
-    srcData += width();
-    destData += width();
-  }
-  return result;
-}
-
-BitmapBuffer * BitmapBuffer::horizontalFlip() const
-{
-  BitmapBuffer * result = new BitmapBuffer(format, width(), height());
-  pixel_t * srcData = data;
-  pixel_t * destData = result->data;
-  for (uint8_t y = 0; y < height(); y++) {
-    for (uint8_t x = 0; x < width(); x++) {
-      destData[x] = srcData[width() - 1 - x];
-    }
-    srcData += width();
-    destData += width();
-  }
-  return result;
-}
-
-BitmapBuffer * BitmapBuffer::verticalFlip() const
-{
-  BitmapBuffer * result = new BitmapBuffer(format, width(), height());
-  for (uint8_t y = 0; y < height(); y++) {
-    for (uint8_t x = 0; x < width(); x++) {
-      result->data[y * width() + x] = data[(height() - 1 - y) * width() + x];
-    }
-  }
-  return result;
-}
-
-BitmapBuffer * BitmapBuffer::loadMaskOnBackground(const char * filename, LcdFlags foreground, LcdFlags background)
-{
-  BitmapBuffer * result = nullptr;
-  BitmapBuffer * mask = BitmapBuffer::loadMask(filename);
-  if (mask) {
-    result = new BitmapBuffer(BMP_RGB565, mask->width(), mask->height());
-    if (result) {
-      result->clear(background);
-      result->drawMask(0, 0, mask, foreground);
-    }
-    delete mask;
-  }
-  return result;
-}
-
-BitmapBuffer * BitmapBuffer::load8bitMaskOnBackground(const uint8_t * lbm, LcdFlags foreground, LcdFlags background)
-{
-  BitmapBuffer * result = nullptr;
-  BitmapBuffer * mask = BitmapBuffer::load8bitMask(lbm);
-  if (mask) {
-    result = new BitmapBuffer(BMP_RGB565, mask->width(), mask->height());
-    if (result) {
-      result->clear(background);
-      result->drawMask(0, 0, mask, foreground);
-    }
-    delete mask;
-  }
-  return result;
-}
-
 FIL imgFile __DMA;
 
 BitmapBuffer * BitmapBuffer::load_bmp(const char * filename)
@@ -1761,18 +1560,6 @@ BitmapBuffer * BitmapBuffer::convert_stb_bitmap(uint8_t * img, int w, int h, int
   return bmp;
 }
 
-uint8_t * BitmapBuffer::loadFont(const uint8_t * lbm, int len, int& w, int& h)
-{
-  int n;
-  unsigned char * font = stbi_load_from_memory(lbm, len, &w, &h, &n, 1);
-  if (!font) {
-    TRACE("load_stb_buffer(%p,%d) failed: %s", font, len, stbi_failure_reason());
-    return nullptr;
-  }
-
-  return font;
-}
-
 #include "../thirdparty/lz4/lz4.h"
 
 LZ4Bitmap::LZ4Bitmap(uint8_t format, const uint8_t* compressed_data) :
diff --git a/radio/src/thirdparty/libopenui/src/bitmapbuffer.h b/radio/src/thirdparty/libopenui/src/bitmapbuffer.h
index 4bb45187c..0ee3f7f3e 100644
--- a/radio/src/thirdparty/libopenui/src/bitmapbuffer.h
+++ b/radio/src/thirdparty/libopenui/src/bitmapbuffer.h
@@ -21,10 +21,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
-#include "opentx_types.h"
 #include "libopenui_defines.h"
-#include "opentx_helpers.h"
-#include "debug.h"
 
 constexpr uint8_t SOLID = 0xFF;
 constexpr uint8_t DOTTED  = 0x55;
@@ -212,6 +209,7 @@ class BitmapBuffer: public BitmapBufferBase<pixel_t>
     ~BitmapBuffer();
 
     void setDrawCtx(lv_draw_ctx_t* ctx) { draw_ctx = ctx; }
+  
     void setData(uint16_t* d) {
       if (!dataAllocated) {
         data = d;
@@ -304,28 +302,18 @@ class BitmapBuffer: public BitmapBufferBase<pixel_t>
 
     void drawAnnulusSector(coord_t x, coord_t y, coord_t internalRadius, coord_t externalRadius, int startAngle, int endAngle, LcdFlags flags = 0);
 
-    void drawBitmapPie(int x0, int y0, const uint16_t * img, int startAngle, int endAngle);
-
     void drawBitmapPatternPie(coord_t x0, coord_t y0, const uint8_t * img, LcdFlags flags, int startAngle, int endAngle);
 
     static BitmapBuffer * loadBitmap(const char * filename, BitmapFormats fmt = BMP_INVALID);
-    static BitmapBuffer * loadRamBitmap(const uint8_t * buffer, int len);
 
     static BitmapBuffer * loadMask(const char * filename);
     static BitmapBuffer * load8bitMask(const uint8_t * lbm);
     static BitmapBuffer * load8bitMaskLZ4(const uint8_t * compressed_data);
 
-    static BitmapBuffer * loadMaskOnBackground(const char * filename, LcdFlags foreground, LcdFlags background);
-    static BitmapBuffer * load8bitMaskOnBackground(const uint8_t * lbm, LcdFlags foreground, LcdFlags background);
-
-    static uint8_t * loadFont(const uint8_t * lbm, int len, int& w, int& h);
-
     uint8_t * to8bitMask(size_t* size) const;
 
     void drawMask(coord_t x, coord_t y, const BitmapBuffer * mask, LcdFlags flags, coord_t offsetX = 0, coord_t width = 0);
 
-    void drawMask(coord_t x, coord_t y, const BitmapBuffer * mask, const BitmapBuffer * srcBitmap, coord_t offsetX = 0, coord_t offsetY = 0, coord_t width = 0, coord_t height = 0);
-
     void drawBitmapPattern(coord_t x, coord_t y, const uint8_t * bmp, LcdFlags flags, coord_t offset=0, coord_t width=0);
 
     coord_t drawSizedText(coord_t x, coord_t y, const char * s, uint8_t len, LcdFlags flags=0);
@@ -336,13 +324,6 @@ class BitmapBuffer: public BitmapBufferBase<pixel_t>
       return drawSizedText(x, y, s, strlen(s), flags);
     }
 
-    coord_t drawTextAtIndex(coord_t x, coord_t y, const char *const *s, uint8_t idx, LcdFlags flags = 0)
-    {
-      return drawText(x, y, s[idx], flags);
-    }
-
-    static void formatNumberAsString(char *buffer, const uint8_t buffer_size, int32_t val, LcdFlags flags = 0, uint8_t len = 0, const char * prefix = nullptr, const char * suffix = nullptr);
-
     coord_t drawNumber(coord_t x, coord_t y, int32_t val, LcdFlags flags = 0, uint8_t len = 0, const char * prefix = nullptr, const char * suffix = nullptr);
 
     template<class T>
@@ -351,12 +332,6 @@ class BitmapBuffer: public BitmapBufferBase<pixel_t>
     template<class T>
     void drawScaledBitmap(const T * bitmap, coord_t x, coord_t y, coord_t w, coord_t h);
 
-    BitmapBuffer * horizontalFlip() const;
-
-    BitmapBuffer * verticalFlip() const;
-
-    BitmapBuffer * invertMask() const;
-
   protected:
     static BitmapBuffer * load_bmp(const char * filename);
     static BitmapBuffer * load_stb(const char * filename, BitmapFormats fmt = BMP_INVALID);