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latexmkrc example how to set pdfcrop for includegraphics
This project demonstrates how the xr package can be used on Overleaf to resolve labels in other .tex files that have not been \include-d in the main file. Make sure you enable the correct system call in latexmkrc, depending on the LaTeX engine you're using!
An example on using pTeX on Overleaf. See this help page and blog post for further details on using pTeX on Overleaf.
This example demonstrates how to write polyphonic or instrumental music on Overleaf, using M-Tx (.mtx) syntax. This was made possible with a custom latexmkrc file. The music piece examples here were taken from the M-Tx documentation.