Datepicker & MutationObserveru - infinite loop

[adros]

Bug description:

When there is a MutionObserver, which observers document.body, there is an infinite loop, when opening Datepicker dropdown.
This is cause by positioning of the modal, executed on zone change (caused by MutationObserver), which temporary resets the dropdown position and thich mutates the body.

Adding this (sample) code will cause the infinite loop.

    const observer = new MutationObserver(function (a) {
      console.log('Body mutated');
    }
    );
    observer.observe(document.body, {
      childList: true,
      subtree: true,
      attributes: true,
      characterData: true
    })

Versions of ngx-bootstrap, Angular, and Bootstrap:

ngx-bootstrap: 20

Angular: 20

Bootstrap: 4