Same problem here.
You write here: (https://www.icegram.com/documentation/es-how-to-add-captcha-in-subscribe-form-of-email-subscribers/)
“How to add captcha in Subscribe form of Email Subscribers
What is Captcha?
CAPTCHA or Completely Automated Public Turing test to Tell Computers and Humans Apart is a technique to distinguish between humans and computers. CAPTCHA is mainly used as a security check to ensure only human users can pass through. Generally, computers or bots are not capable of solving a captcha.
You would need latest versions of following plugins installed & activated on your site to enable captcha :
Email Subscribers (free) Email Subscribers (Pro)”
But if I want to enable captcha, it doesn’t work.
I’ve installed the newest version of your plugin, afterwards I tried and entered some email-adresses that I just typed without any giving sense.
They all were entered.
No spam prevention at all.