Is the theory here that the browser cannot be co-opted to infect web-based repositories? Also: thinking of how yt-dlp can integrate with browser cookies now and the malware paths that opens up. (This is part of why Chrome wants HSM cookies, I expect: DRM and opsec!)
In this scenario the malware will not be on the device but in an isolated dev environment on a remote machine. So it will have access to whatever was configured in that repo but hopefully the project is isolated enough to ensure containment and prevent cross-pollination.