How to use
For all captchas:
[Esc] key acts like the "Skip" button.
[Ctrl] + [+]/[-] changes the scale for the current captcha.
You can specify the default value for new captchas in the settings.
For text captchas only:
[Enter] key acts like the "Send" button.
[Ctrl] + [Enter] key acts like the "Send, then Stop" button.
For mouse captchas only:
[Ctrl] + click acts like clicking the captcha, then the "Stop" button.