Problem with shadow in tcolorbox with LaTeX compilation

I'm using TeX Live 2019 with LaTeX compiler (in Overleaf). I have the following code:

\documentclass[border=2mm]{standalone}

\usepackage[many]{tcolorbox}

\begin{document}
{This is a tcolorbox.}
\end{document}


but I obtained

By using pdfLaTeX compilation with TeX Live 2019 or LaTeX compilation with Tex Live 2017, I obtain the right result:

What could be the problem? How can I fix it?

• With recent MikTeX installation (pdfTeX, Version 3.14159265-2.6-1.40.21 (MiKTeX 20.7)) i obtain right result. You probaly need to upgrade your TeX Live to version 2020. – Zarko Aug 15 '20 at 5:39
• @Zarko I'm using Overleaf – MateAndres Aug 15 '20 at 5:50
• Ah, Overleaf is not always up-to-date with packages versions.Unfortunately. – Zarko Aug 15 '20 at 6:00
• Does latex mean you are using dvips and ps2pdf? – Ulrike Fischer Aug 15 '20 at 7:39
• @Zarko It's not a package problem, it's a Ghostscript problem (tex.stackexchange.com/questions/453780/…) – MateAndres Aug 15 '20 at 19:27

You should be able to allow transparency by adding a new file latexmkrc (without any file extension) into your project's top folder and adding the following line there:
\$dvipdf = "dvipdf -dNOSAFER -dALLOWPSTRANSPARENCY %O %S %D";