Why does mtpro2 lite font only work in Overleaf in some cases?

Question

I want to use the mtpro2 package in Overleaf but it seems to work only in some cases.

If I go to "new project", "blank project" and use this:

\documentclass[]{article}

\usepackage{lipsum}

\usepackage[lite]{mtpro2}

\begin{document}

\lipsum

\end{document}

it says the mtpro2.sty file was not found. However, if I use the template

https://es.overleaf.com/latex/examples/using-mtpro2-lite-fonts/ycyvptpzmkjf

and simply copy and paste the above it works perfectly.

I see no reason why Overleaf will find the package in one case and not in the other. In particular, in both cases, I am using pdfLaTeX compiler. It's starting to get a little annoying not finding the reason why it doesn't work.

PS. The template project doesn't have any other file in it, just the single tex file.

Edit: Apparently for some people it was working, so I created a public project to show the error. https://www.overleaf.com/3449315768tszmmrnmspcs

Answer 1

(I'm on support staff at Overleaf.)

Since the template project was created in Overleaf v1, the new project based on the template is automatically created using Overleaf v1's TeX Live 2016 image, which includes certain non-free fonts, including MTPro2 Lite. (Even though the font is "free as in free beer" it doesn't meet all the criteria of free/libre software in order to be included in TeX Live outright.)

When creating a new blank project, the newer Overleaf v2 (from the merger with ShareLaTeX) compiler image is used. (This is currently TeX Live 2017, but we will be releasing an updated image in the coming months.) This compiler image does not include the non-free fonts.

As a workaround, you might instead use \usepackage{newtxtext, newtxmath} from the newtx package, a more robust and updated free version of the TX fonts.