Disclaimer: I realize you cannot support compatibility with all other plugins, just trying to get some additional information, and can’t hurt to ask.
So, I was attempting to use this plugin: https://wordpress.org/plugins/google-apps-login/
Which adds a second login option of “login with google” to the login page.
I discovered that while the recaptcha from your plugin was enabled, then if I attempted to login with google, wordpress would just give an “invalid username or password!” error. After disabling captcha for the login page, it worked just fine.
Is this error probably caused by the captcha failing because its logging in via a separate entity?
Don’t suppose there’s a way to get your plugin to detect this sort of situation?
(Note: while the google apps login plugin does provide an option to somewhat force google login, I need people to be able to login normally too so, that’s why I’d like to keep the captcha as well)