OpenTitles is a free browser add-on developed by Floris de Bijl that allows users to track changes to news headlines on over 40 different news sites. This Chrome extension adds a button to the headlines on these sites, and when clicked, it displays all recent changes to the title of the article.

The main purpose of OpenTitles is to provide users with a convenient way to monitor changes to news headlines without having to manually check each website. This can be particularly useful for individuals who rely on up-to-date news information or for those who are interested in tracking specific topics or events.

One question that may arise when installing this add-on is why Chrome requires it to read browser history. The answer to this is that the "tabs" permission is needed for the add-on's popup to determine which website the user is currently viewing, in order to determine whether the OpenTitles API is already tracking that website or not. It is important to note that this add-on does not actually read the user's browser history, as confirmed by reviewing the OpenTitlesMainScript.js file in the installation.