Hello and thank you for developing this tool. I've encountered an issue with subkey generation. It appears the tool incorrectly resolves the existence of GNUPGHOME on macOS (11.0.1).

> trezor-gpg init "First Last" --verbose --subkey
...
2020-12-14 17:15:06,093 INFO         device name: trezor                                                                                  [__init__.py:126]
2020-12-14 17:15:06,093 INFO         GPG home directory: /Users/user/.gnupg/trezor                                                              [__init__.py:131]
2020-12-14 17:15:06,093 ERROR        GPG home directory /Users/user/.gnupg/trezor exists, remove it manually if required                        [__init__.py:134]

Am I missing something here? The directory exists because the master key generation created it. Master key generation worked as expected, though setting up a separate keyring in a subfolder seems counter-intuitive. If you remove the directory, the subkey mode generation proceeds and stop later after failing to find the master key (for obvious reasons). I'm guessing there is an issue with the subkey mode of the app, perhaps the fact that I'm using long names for user_id (which should be supported). Version:

> trezor-gpg --version
trezor-agent=0.11.0 libagent=0.14.1