Open Source Contributions vs Personal Project

I know there are past threads on this, but I felt like it could use a bit more discussion.

In terms of resume building, what would look better? Contributing to existing, known open source projects or doing a personal project from scratch? Given that you maybe only have time to do one

My thoughts:

Open source - If it's a popular project like mozilla or python, it could look good on your resume if you have accepted pull requests. On the other hand, the more popular the project, the more likely your contributions will be very very small, such as fixing minor bugs or doing documentation.

Personal Project - Since you get to build it from scratch you get a lot more experience with software design and coding in general. Your contributions will be building an entire app or whatever it is, rather than just fixing a few bugs. On the other hand, nobody will have heard of your project.

TLDR: What will make your resume stand out to recruiters more, small contributions (bug fixes probably) to well-known open-source projects or building your own personal project from scratch.