go to new Thread activity only if it is different than the current

app/src/main/kotlin/com/simplemobiletools/smsmessenger/activities/ThreadActivity.kt

@@ -152,14 +152,16 @@ class ThreadActivity : SimpleActivity() {
             thread_add_contacts.beGone()
 
             val numbers = participants.map { it.phoneNumber }.toSet()
-            val threadId = getThreadId(numbers).toInt()
+            val newThreadId = getThreadId(numbers).toInt()
+            if (threadId != newThreadId) {
                 Intent(this, ThreadActivity::class.java).apply {
-                putExtra(THREAD_ID, threadId)
+                    putExtra(THREAD_ID, newThreadId)
                     addFlags(Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TOP)
                     startActivity(this)
                 }
             }
         }
+    }
 
     private fun blockNumber() {
         val baseString = R.string.block_confirmation