Clicking annotations doesn’t navigate away from your site to a Google search; it triggers an overlay with infoboxes about the term you selected. It’s similar to the iOS “Look Up” option for selected text. It’s wrong to do because this obfuscates what is and isn’t a link the author placed on the page. Inserting what appears to be links into the page crosses the line from user-agent interventions, such as adblocking or turning off certain unsafe features (acceptable) to editing an a...
