Yarick

This plugin notifies user if browser check failed. Available checks:
<ul>
<li>Browser version (Chrome, Firefox, Safari, Opera, IE)</li>
<li>JavaScript enable</li>
<li>Cookie enable (require JavaScript)</li>
<li>Adobe Flash Player version (require JavaScript)</li>
</ul>
You can select style for notice. Or disable plugin CSS and write own.
User can close notice to time you set in minutes. It use cookie. You can disable close button.
Also you may set next check time in days. When check is successful.
Browser Check may be integrated with theme. Just place this code: “do_action(‘browser_check’)” in your theme. And disable plugin css from “Settings -> Browser Check” page and write own css for best look in your theme.
Supported languages
<ul>
<li>English</li>
<li>Russian</li>
</ul>

Browser Check

Check browser version, JavaScript, Cookie, Adobe Flash Player version. Warn user if old.

Paolo Rossi (Ipalo)

Checkmail Validation for Contact Form 7 add the double check email field to your form and verify email match with the CF7 Ajax validation.
<h4>Double email check</h4>
This plugin add a new field in Contact Form 7 called “Checkmail” that allow to do a double email check when submitting the form. The new field will ask to users to confirm their email by typing it into a second field.
If you want to do this in your form, you only have to add the “Checkmail” field into the CF7 form and enter the email field name you want to check. The validation is done by the CF7 Ajax-powered style: when submitting form CF7 will do the double email check, if not match returns error and ask to users to verify the email addresses.

Checkmail validation for Contact Form 7

Add a double email check field to Contact Form 7.

Browser Check vs Checkmail validation for Contact Form 7