cobianzo

This is a very simple plugin that allows you to associate a tooltip to any link in the block editor. 
Open the link options, click on the pencil icon to edit it, then make sure that the Advanced panel 
is open, and find the new input box for the tooltip. 
You will see the tooltip when you hover with the mouse the link in the frontend.
Main features: 
– new ‘tooltip’ input box in the CMS editor ‘edit link’, under ‘Advanced’ tab. 
– showing this new field as a simple CSS-only tooltip in the frontend 
– CSS rules use some variables to easily modify the aspect of the tooltip.

GB CSS Tooltip

Simple functionality that includes an extra option when editing a link within the block editor: nice CSS tooltips.

The DomainTools Whois plugin will automatically link domain names in a WordPress page or blog post to the DomainTools Whois service. It also generates a pop-up containing a summary of Whois information that your visitors can see without leaving your site.

DomainTools Whois Plugin

DomainTools whois plugin shows whois data for domains found in blog articles and links them to whois.domaintools.com.

GB CSS Tooltip vs DomainTools Whois Plugin