Move the condition before the loop

Result see: https://youtu.be/AEnBzdu9_tk
Dot is moving not so fast -> less executed loops.

Marlin/ultralcd.cpp

@@ -1363,16 +1363,18 @@ void lcd_update() {
     #ifdef DOGLCD  // Changes due to different driver architecture of the DOGM display
       blink++;     // Variable for fan animation and alive dot
       u8g.firstPage();
-      do {
-        if (!dotcounter) dotcounter = 63;
-        lcd_setFont(FONT_MENU);
-        u8g.setPrintPos(125, 0);
-//        if (blink % 2) u8g.setColorIndex(1); else u8g.setColorIndex(0); // Set color for the alive dot
-        u8g.drawPixel(127, dotcounter--); // draw alive dot
-//        u8g.setColorIndex(1); // black on white
-        (*currentMenu)();
-        if (!lcdDrawUpdate) break; // Terminate display update, when nothing new to draw. This must be done before the last dogm.next()
-      } while( u8g.nextPage() );
+      (*currentMenu)();
+      if (lcdDrawUpdate) {
+        do {
+          if (!dotcounter) dotcounter = 63;
+          lcd_setFont(FONT_MENU);
+          u8g.setPrintPos(125, 0);
+  //        if (blink % 2) u8g.setColorIndex(1); else u8g.setColorIndex(0); // Set color for the alive dot
+          u8g.drawPixel(127, dotcounter--); // draw alive dot
+  //        u8g.setColorIndex(1); // black on white
+          (*currentMenu)();
+        } while( u8g.nextPage() );
+      }
     #else
       (*currentMenu)();
     #endif