![Trying to use my late 2013 Mac 21.5” as a second display for my 2020 Mac 27”. Smaller mac won't go into target display mode. Has anyone come across this issue? : r/mac Trying to use my late 2013 Mac 21.5” as a second display for my 2020 Mac 27”. Smaller mac won't go into target display mode. Has anyone come across this issue? : r/mac](https://preview.redd.it/hwjicedel8a61.jpg?auto=webp&s=182f1a717bbed1fc16c00e0ef0d3d74522acac50)
Trying to use my late 2013 Mac 21.5” as a second display for my 2020 Mac 27”. Smaller mac won't go into target display mode. Has anyone come across this issue? : r/mac
![Target Display mode is pretty Universal on the 27 inch iMacs from 2009 & 2010 with only a mini display port connection required. : r/mac Target Display mode is pretty Universal on the 27 inch iMacs from 2009 & 2010 with only a mini display port connection required. : r/mac](https://preview.redd.it/target-display-mode-is-pretty-universal-on-the-27-inch-v0-41x7p7f5y50a1.jpg?width=640&crop=smart&auto=webp&s=8e26c23caa963c1dbb9bb2475ad6d61fa4d5ca4d)
Target Display mode is pretty Universal on the 27 inch iMacs from 2009 & 2010 with only a mini display port connection required. : r/mac
![Review: Apple's 21.5" iMac with Retina 4K display gets solid 2017 architectural refresh | AppleInsider Review: Apple's 21.5" iMac with Retina 4K display gets solid 2017 architectural refresh | AppleInsider](https://photos5.appleinsider.com/gallery/21707-25280-FullSizeRenderjpg-2-xl.jpg)
Review: Apple's 21.5" iMac with Retina 4K display gets solid 2017 architectural refresh | AppleInsider
![Retina 5K iMac Will Not Act as External Display, Standalone Apple 5K Display Unlikely Soon - MacRumors Retina 5K iMac Will Not Act as External Display, Standalone Apple 5K Display Unlikely Soon - MacRumors](https://images.macrumors.com/t/CgJkFavftePzDJ2-mp3Gi4FCi7g=/1600x1200/smart/article-new/2014/10/imac_retina_waterfall.jpg)