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New ABS customer's Experience with OS X and Safari versus Firefox: A comment
For this Mac user with OS X Catalina, the FastTrack and Fundamentals videos show up poorly in Firefox, but very nicely in Safari. In Firefox, the progress bar does not show well, so it is difficult to back up and review while the video is running. It works properly in Safari. The interface has an elegant appearance in Safari, but appears washed out in Firefox. I recommend trying Safari immediately, not after watching a dozen videos as I did.