Seems noob question but I couldn't spot the difference between Fira Code and Fira Code Retina. Is it somehow related to retina display or what? Difference is missing in the Wiki also.
From my own experience the Retina version is meant to provide better support on Apple Retina displays. I tend to use the non Retina version since I use none Retina displays connected to my MacBook and find it slightly more blurry on non Retina but apart form that can't visually notice a difference between the two versions. However I suspect people that are hyper aware of fonts would notice a difference. I suspect if it's the only type of display you use it will be a better default choice.
Retina is just sliiiightly bolder than Regular. I called it Retina because on Retina fonts seems a bit thinner than on non-retina screens, so it compensates just for that. Traditionally a weight between Regular and Medium is called Book (or Text), but I decided, if the font is for 21-st century and for screen use only, we should not use books in the name.

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Retina is just sliiiightly bolder than Regular. I called it Retina because on Retina fonts seems a bit thinner than on non-retina screens, so it compensates just for that. Traditionally a weight between Regular and Medium is called Book (or Text), but I decided, if the font is for 21-st century and for screen use only, we should not use books in the name.