You should always opt to do this, or even configure yay to automatically show them in ~/.config/yay/config.json. yay asks you if you want to see the diffs before building. You have to check the contents of the PKGBUILD and especially the source array to see what it downloads and uses. Some of them build from source code like brave, but others download prebuilt binaries and package them like brave-bin. If you’re not convinced, just click on the Brave icon and see the many ads, trackers, and scripts blocked over time. With the ad-free browsing, Brave ensures that your data and privacy remains secure from third parties. The AUR contains user-submitted packages so you have to check their contents and verify that they are ok! Also, these packages are not pre-built, they are scripts that build packages locally on your system. Of course, faster speed does not mean less safety. Yay can do the above, because it wraps pacman, but it also uses the Arch User Repository (AUR).

That means you can expect it to work relatively smoothly and you can trust the contents of the package to a high degree.

Pacman only downloads pre-built packages from specified repositories, which by default are the official repos of arch linux. The equivalent of apt on arch is pacman, not yay!

Brave browser download