I needed to reinstall Firefox on this computer, so I started up Chrome to download the latest version and it blocked the download as unsafe! I had to manually tell it to download anyway.
Fuck Chrome. I'm glad I only used it to download one file and went back to Firefox.
iirc there's a mac setting in systems prefs where you can allow apps to be downloaded from the app store or the app store and unverified developers. by default i believe they have it set to app store only. (system prefs > security & privacy > general)