struct { 
  ...
    // other variable
  uint8_t connect_flag;  // =1 if wire connected, else =0 
  uint8_t current_page;

} RemoteXY;

But our suggestions seems to be ignored...

2) Add two Page elements, then when you add another element you can choose on which page it must be displayed, or if it must be displayed on all Pages. Click on a Page element to go to that Page.

3) Not possible..

As you see actually it's 29:

255,2,0,29,...

Which is 8 + 21.

This byte must match the total of the sizes of these arrays. If total is more than 255, then the fifth byte must also be increased (it's a 16 bits value so it is split in two bytes).

Here is the part corresponding to these arrays:

67,5,4,9,55,13,16,201,8  // text_1
67,5,4,24,55,9,16,201,21 // text_2

The last number of each line must match the size of the array in the RemoteXY struct

Want to know more about manual modification, read this topic, it is outdated, things changed, but it should still be relevant in most cases

char text_1[30];  /* string end zero UNICODE */ 
char text_2[22];

Did you manually modify the sizes of these arrays ? According to the values in RemoteXY_CONF, their size should be 8 and 21, not 30 and 22.

/* RemoteXY connection settings */ 
#define REMOTEXY_SERIAL Serial
#define REMOTEXY_SERIAL_SPEED 115200 
#define REMOTEXY_WIFI_SSID "Project"
#define REMOTEXY_WIFI_PASSWORD "12345678"
#define REMOTEXY_SERVER_PORT 6377

/* RemoteXY configurate  */ 
#pragma pack(push, 1)
uint8_t RemoteXY_CONF[] =
  { 255,2,0,29,0,123,0,8,33,1,
  130,1,1,0,61,36,82,130,1,1,
  38,61,30,82,129,0,9,1,46,6,
  8,84,69,77,80,69,82,65,84,85,
  82,69,0,67,5,4,9,55,13,16,
  201,8,67,5,4,24,55,9,16,201,
  21,129,0,19,40,25,6,8,72,69,
  65,84,69,82,0,2,1,6,48,50,
  16,1,26,31,31,79,78,0,79,70,
  70,0,130,1,1,70,61,29,82,129,
  0,19,72,26,6,8,67,79,79,76,
  69,82,0,2,1,7,80,49,16,135,
  26,31,31,79,78,0,79,70,70,0 };
   
/* this structure defines all the variables of your control interface */ 
struct { 
   
     /*input variable*/
  uint8_t switch_1; // =1 if switch ON and =0 if OFF
  uint8_t switch_2; // =1 if switch ON and =0 if OFF
   
    /* output variable */
  char text_1[30];  /* string end zero UNICODE */
  char text_2[22];
 
    /* other variable */
  uint8_t connect_flag;   /* =1 if wire connected, else =0 */

} RemoteXY; 
#pragma pack(pop)

#define PIN_SWITCH_1 13
#define PIN_SWITCH_2 12

void setup()   
{ 
  RemoteXY_Init ();
  pinMode (PIN_SWITCH_1, OUTPUT);
  pinMode (PIN_SWITCH_2, OUTPUT);         
} 
void loop()   
{   
  RemoteXY_Handler (); 
  /* get the ADC value */
  int sensorValue = analogRead(A0);     
  double mv = (sensorValue/1024.0)*5000;
  double temp = mv/10;
  dtostrf(temp, 0, 2, RemoteXY.text_1);
  if(temp>=25.00)
  {
    sprintf(RemoteXY.text_2,"HEATER");
  }
  else
  {
sprintf(RemoteXY.text_2,"COOLER");
  }
  /*convert the temperature value into a string 
    and place it immediately in the field text_1 patterns RemoteXY 
  */ 
  Serial.print("TEMPERATURE = ");
  Serial.print(temp);
  Serial.print("*C"); 
  Serial.println();
  delay(1200);       

digitalWrite(PIN_SWITCH_1, (RemoteXY.switch_1==0)?LOW:HIGH);
  digitalWrite(PIN_SWITCH_2, (RemoteXY.switch_2==0)?LOW:HIGH);
}