I bought the DVDs. It used Adobe Air which I had never heard of and is discontinued. Each page of the magazine is in some encrypted format but I found software on the internet to decrypt it. You can use cp to get those files. Then you can google about the encryption.
My parents got me a subscription in 1987 when I was a kid and I'm still a print edition subscriber and linked my online account to my subscription. I can read any issue online as well and print to PDF so I do that every couple of months so I have every issue from 1888 to 2023.
Adobe AIR was a precursor to Electron in the late 00s. It allowed apps written in JavaScript, ActionScript and some other Adobe tech to be easily built for multiple platforms.
The Adobe Air program was basically just a front end to display and decrypt everything. I could never get it to work on Linux so I never actually even looked at it except the screenshots in the help document.
All the files are named well like NGM_1918_04_125.jpg
National Geographic Magazine, year 1918, 4th month (April), page 125
Yeah, it was annoying but I ran a for loop on every file in the 80GB or so to translate it to normal JPEG. It took about 24 hours and that was 10 years ago on a much older computer.
My parents got me a subscription in 1987 when I was a kid and I'm still a print edition subscriber and linked my online account to my subscription. I can read any issue online as well and print to PDF so I do that every couple of months so I have every issue from 1888 to 2023.