Opencv.js --threads how to compleatly release memory when refreshing page?

Hi,

How to completely release memory when an application terminates? For example, when refreshing a page or moving to the another page?

The error (not enough memory) only occurs when refreshing a page with the **multi-threaded version** of opencv (build with --threads flag) and does not occurs with the single-threaded version. And only on devices with 3 GB of RAM.

I tried release memory like this, but it didn't help:
```
window.onbeforeunload = function()
{
if (cv.PThread !== undefined)
{
cv.PThread.terminateAllThreads();
cv.__emscripten_thread_free_data();
}
}
```
It seems that the memory is not release or it does not release immediately on page refresh. Therefore, when opening the application again in the same tab, an error occurs.

P.S.
I had exactly the same error with Tensorflow.js. It was successfully resolved after memory was released on the window.onbeforeunload event. There the memory release function looks like this:
```
TFLiteWebModelRunner.prototype.cleanUp=function()
{
if(null!=this.cppClassifier)
{
for(var a=$jscomp.makeIterator(this.memOffsetsToFree),b=a.next();!b.done;b=a.next())
this.module._free(b.value);
this.cppClassifier.delete()
}
};
```

Is there the same function in opencv.js?
Is there a way to simply reset the wasm memory when the application terminates?