If you're using this code snippet as a reference, keep in mind that there may be other issues to address. Make sure you have all the necessary CSS code for dropdown functionality.
Simply adding classes without understanding how Bootstrap 4 works can lead to future problems. Take the time to learn how flex works, especially when nesting <div> elements with classes.
Check out these resources to better understand flex:
https://www.w3schools.com/bootstrap4/bootstrap_flex.asp
https://getbootstrap.com/docs/4.3/utilities/flex/
By mastering flex in Bootstrap 4, your coding experience will be much smoother. Happy coding!
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<div class="d-flex justify-content-between" style="background:black">
<div></div>
<div>
<h2 class="text-center" style="color:white">Resultado de aprendizaje A</h2>
</div>
<div class="dropdown mr-3">
<button class="btn btn-outline-light" type="button" id="dropdownMenu2" data-toggle="dropdown"
aria-haspopup="true" aria-expanded="false">
<i class="fa fa-ellipsis-h p-1" style="font-size: 18px"></i>
</button>
<div class="dropdown-menu" aria-labelledby="dropdownMenu2">
<a class="dropdown-item" data-toggle="modal" data-target="#resultadoModal}edit">Editar</a>
<button class="dropdown-item" >
Eliminar
</button>
</div>
</div>
</div>