Interactively capture and inspect third-party trackers encountered while browsing.
Brightbeam is a browser extension for Firefox-based browsers.
Brightbeam is a continuation/fork of Mozilla Lightbeam, a Firefox extension made to "help users understand the array of first and third party companies people interact with every day across the Web". Lightbeam was discontinued by Mozilla in 2017. Because its functionality is quite useful for people who wish to research trackers (rather than block them), Brightbeam seeks to build upon Lightbeam to offer functionality specifically for that purpose.
While active, Brightbeam keeps track of what sites you visit, and what external content those sites load. Known trackers can be identified and the aggregate data can be exported to study with external tools like Gephi. The extension can be downloaded from the linked Github repository's "Releases" page.