I assumed you are using the FastLED variant, so here the modified Strobe code (untested, since I have no hardware laying around at the moment to test this):
#include "FastLED.h"
#define NUM_LEDS 60 
CRGB leds[NUM_LEDS];
#define PIN 6 
byte red = 0xff;
byte green = 0xff;
byte blue = 0xff;
int numberOfFlashes;
int delayBetweenFlashes;
int pauseAfterEffect; 
void setup()
{
  FastLED.addLeds<WS2811, PIN, GRB>(leds, NUM_LEDS).setCorrection( TypicalLEDStrip );
  randomSeed(analogRead(0));
}
//  REPLACE FROM HERE 
void loop() { 
  numberOfFlashes=random(10);  // random number between 0 and 10
  delayBetweenFlashes=random(100);  // random number between 0 and 100
  pauseAfterEffect=random(1000);  // random number between 0 and 1000
  Strobe(red, green, blue, numberOfFlashes, delayBetweenFlashes, pauseAfterEffect);
}
void Strobe(byte red, byte green, byte blue, int StrobeCount, int FlashDelay, int EndPause){
  for(int j = 0; j < StrobeCount; j++) {
    setAll(red,green,blue);
    showStrip();
    delay(FlashDelay);
    setAll(0,0,0);
    showStrip();
    delay(FlashDelay);
  }
 
 delay(EndPause);
}
//  REPLACE TO HERE 
void showStrip() {
 #ifdef ADAFRUIT_NEOPIXEL_H 
   // NeoPixel
   strip.show();
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H
   // FastLED
   FastLED.show();
 #endif
}
void setPixel(int Pixel, byte red, byte green, byte blue) {
 #ifdef ADAFRUIT_NEOPIXEL_H 
   // NeoPixel
   strip.setPixelColor(Pixel, strip.Color(red, green, blue));
 #endif
 #ifndef ADAFRUIT_NEOPIXEL_H 
   // FastLED
   leds[Pixel].r = red;
   leds[Pixel].g = green;
   leds[Pixel].b = blue;
 #endif
}
void setAll(byte red, byte green, byte blue) {
  for(int i = 0; i < NUM_LEDS; i++ ) {
    setPixel(i, red, green, blue); 
  }
  showStrip();
}
Give it a try and let me know how this worked out so we can continue from there ...