

I think that at some point, my computer had run out of application memory which might be how I got into this situation because I had previously created another fluid app which I had been able to paste an icon onto in the usual way.

Note, I had tried pasting images into the get info window of type png, tiff, pict, icns, and various correctly sized versions of these formats. I had to then go into "Get Info" again and paste literally any image and it then updated to the image I'd saved as appl.icns in /Contents/Resources. UNetbootin is extremely fast and is a great Rufus alternative for flashing macOS, Windows, Ubuntu or any other Linux distro. It’s designed mainly to create Linux-based bootable USB drives from any machine but works perfectly on macOS. Launch the terminal app (You can find this by searching for 'terminal' with the spotlight search in the upper right of your screen. Launch the RedQuits app again, and check all three checkboxes when prompted. This did not change the appearance of the app's icon immediately. UNetbootin works on Mac, Ubuntu and other Linux distributions. Click the lock in the bottom left corner to make changes, then click the ReQuits checkbox in the right pane. I then named the file "appl.icns" and dragged it into the resources folder. There was no appl.icns file there, so I converted my image to icns format using the image2icon app (free from the mac app store). I went into the subfolder Contents->Resources. To fix this, I right-clicked the app and selected "Show Package Contents". megabytes on disk), but the icon still did not appear.

So I went to "get Info" on the app and when I clicked the icon at the top and tried to paste the copied image, the size of the app changed (i.e. I had selected an image in Fluid to use as the app icon, but it didn't work. I had an app I'd created using Fluid.app. I don't know if you were having the same problem I just was facing, but here's what was happening to me and how I fixed it.
