9000 internet cookie points to whoever figures out this shit:

I'm trying to import a secret gpg key into my keyring.
If I run "gpg2 --import secring.gpg" and manually type each possible password that I can think of, the import fails. So far, nothing unusual.
HOWEVER
If I type the same passwords into a file and run:
echo pwfile.txt | gpg2 --batch --import secring.gpg
IT ACTUALLY FUCKING WORKS

What the fuck??? How can it be that whenever I type the pw manually it fails, but when I import it from a file it works??
And no, it's not typos: I could type those passwords blindfolded from muscle memory alone, and still get them right 99% of the time. And I'm definitely not blindfolded right now.

BUT WAIT, THERE'S MORE!!

Suppose my pwfile.txt looks something like this:

password1
password2
password3
password4
password5
password6

Now, I'm trying to narrow it down and figure out which one is the right password, so I'm gonna split the file in two parts and see which one succeds. Easy, right?

$ cat pw1.txt
password1
password2
password3

$ cat pw2.txt
password4
password5
password6

$ echo pw1.txt | gpg2 --batch --import secring.gpg
gpg: key 149C7ED3: secret key imported

$ gpg2 --delete-secret-key "149C7ED3"
[confirm deletion]

$ echo pw2.txt | gpg2 --batch --import secring.gpg
gpg: key 149C7ED3: secret key imported

In other words, both files successfully managed to import the secret key, but there are no passwords in common between the two!!
Am I going retarded, or is there something really wrong here? WTF!

Yesterday and today combined I spent about 8 hours trying to get my PGP / GPG passphrase to work. Absolutely magically, somehow a newline character had gotten into the passphrase. Yes. That's possible. On macOS, that is.

On my Windows machine I have the same fucking private key protected with the same password. Now try and get a non-windows newline character into any Windows password field, be it a command line or some GUI input. WTF! You'll lose a year of your life with every passphrase error while you have the actual passphrase.

So after all these hours trying to hack my own GPG keystore without success, I remembered how the private key got on my Windows machine in the first place: see tags.