Mailster - Email Newsletter Plugin for WordPress 4.1.7

fixed: escaped content on edit screen.
fixed: escaped several strings.
improved: United Kingdom is no longer part of the European Union.

improved: CSS for WordPress 5.3
improved: action type is now returned in form submission
improved: form submission on errors
fixed: content type selection not respected on dynamic insertion mode
fixed: ERR_CONNECTION_RESET issue on some Apache installations

• tested with WordPress 5.3
• fixed: potential XSS vulnerable on the subscribers detail page identified by Compass Security
• fixed: single quote in subject now correctly encoded
• fixed: confirm redirection issues on some installations
• change: Redirect after submit and Redirect after confirmation must be a URL