If an old device works, it is not necessarily safe
Sometimes it can seem that any (even old) device that is functional is suitable for the job. However, this assumption is often wrong.
For FF employees, we have PRO licenses for Overleaf, which is used for typesetting and editing texts in LaTeX. This is often used for academic papers and other professional texts. The PRO license benefits from the ability to collaborate on publications in the cloud, conveniently in a browser environment. It is also free of file capacity limits and has integration with git and github.
If you're interested in a license, register as described on the Overleaf web-based LaTeX document editor page, where you'll also find more details.