I have an older compiled application that is not yet running in Retina mode. Now I found the Xojo blog post Enabling Retina Support and inserted the following code into the Info.plist file as described.
If I now start the program, it still appears in the low resolution. I have read that the cache of the application needs to be refresh. Therefore you should enter the following command in the macOS terminal:
sudo touch /Applications/Appname.app
However, the application still does not start in Hi-DPI mode. How do I get the desired result?