When you stumble on websites, especially those “security-conscious” ones, that stops you from pasting passwords, you know they are rather irritating, and plain idiotic.
Allow your website to accept pasted passwords - it makes your site more secure, not less.
Here is an article from the National Cyber Security Center on why allowing password pasting is a much safer way – Let them paste passwords.
The main reason why password pasting improves security is because it helps to reduce password overload. Allowing the pasting of passwords makes web forms work well with password managers. Password managers are software (or services) that choose, store and enter passwords into online forms for you.
Password managers are very useful because they:
Here is a very nice article from the Security Expert, Troy Hunt, The “Cobra Effect” that is disabling paste on password fields that details on why not to stop using the idea of not allowing password-pasting on websites.