How to track emails sent using google app script?

Question

I use google sheets to track sales contacts. I use a simple google app script to automatically send emails to all the people listed in the spreadsheet.

I also use services like streak and mailtrack to track my emails (ie know that it the recipient has viewed it)

The problem is that both these plugins are chrome extensions. So I noticed that they work fine if I send an email manually through gmail on chrome. However when I send mass emails using the above script, these tracker tools are oblivious.

Any ideas?

Update

I tried sending the email using GmailApp, but didn't work either:

std::mutex mu;
int foo = 0;  // Guarded by mu
std::atomic<bool> foo_has_been_set{false};

void SetFoo() {
  mu.lock();
  foo = 1;
  foo_has_been_set.store(true, std::memory_order_relaxed);
  mu.unlock();
}

void CheckFoo() {
  if (foo_has_been_set.load(std::memory_order_relaxed)) {
    mu.lock();
    assert(foo == 1);
    mu.unlock();
  }
}