Docker password store in .docker/config.json

docker base64

When you manually base64-encode strings at the command line, you need to be careful to not include a newline. echo -n is helpful for this.

$ echo -n '@' | base64QA==

This matches what's in your .docker/config.json file. If I decode your other string

$ echo -n 'QAo=' | base64 -D | od -t x10000000    40  0a

it contains two bytes, ASCII 0x40 (@) and 0x0a (newline).

CodeHunter