I just tried to download a firmware file for Homematic using the browser as usual. However, every time I tried to flash the firmware file, I received an error message stating that the file did not contain valid firmware. I found a suggestion online to download the file not through a browser but through the command line using wget. However, wget is not available by default on Mac OS X, so I needed an alternative solution.
One option is to install wget using Homebrew, a package manager for Mac OS X. However, a much simpler solution is to use curl instead.
To download the file, simply use the Terminal, navigate to the desired folder, and execute the following command:
curl FILE_TO_DOWNLOAD -o LOCAL_FILENAME
For example:
curl http://example.com/file-to-download.tar.gz -o file-to-download.tar.gz
Using this method, the file was downloaded correctly, and I was able to apply the update.