Offlinetags at the Chemnitz Linux Days
Who decides how your own image ends up on the internet? At the 2026 Chemnitz Linux Days (CLT) (https://chemnitzer.linux-tage.de/2026/de/) on March 28 and 29, 2026, every visitor had this choice—in a very concrete and clearly visible way. For the first time at the CLT, so-called Offlinetags (https://offlinetags.github.io/) were used, a research project by EXDIGIT Professor Frank Pallas (https://pepsys-group.github.io/team/fp). The Offlinetags consist of four colored symbols that communicate personal photo preferences at a glance:
– “No Photos” — Please do not take any photos of me, even if I do not appear to be identifiable to the viewer of the image.
– “Blur me” — Please ensure, before uploading or publishing any image of me, that I am not easily recognizable—especially not through facial recognition technology.
– “Upload me” — Uploading and publishing images of me is permitted. Please refrain from tagging and using image recognition technology.
– “Tag me” — You may photograph me, publish the images, tag them, and use facial recognition technology.
The concept underscores the CLT 2026 motto: Sovereign Digitality. The two-day conference focused on open source, Linux, and free software is one of the largest of its kind in the German-speaking world, attracting around 3,800 attendees. The program included presentations, workshops, and an exhibition area for companies and open-source projects. EXDIGIT members Frank Pallas and Nicola Leschke contributed to the program with the presentation “(No) Photos Please!” (https://media.ccc.de/v/clt26-325-keine-fotos-bitte) and a lightning talk (https://media.ccc.de/v/clt26-63-lightning-talks) about the Offlinetags.
CLT 2026 was the first known use of Offlinetags at an event without a focus on data protection; therefore, the two EXDIGIT members and a team led by Dr. Albrecht Kurze (https://www.tu-chemnitz.de/informatik/mi/mitarbeiter/albrecht-kurze.php) from the Department of Media Informatics at Chemnitz University of Technology accompanied this implementation with a three-part study: over 170 CLT attendees participated in the preliminary study, the team conducted over 100 interviews during the event, and the follow-up study (https://bildungsportal.sachsen.de/umfragen/limesurvey/index.php/336913?newtest=Y&lang=de) is still ongoing throughout April.
Thank you very much for the extensive feedback! The results will be used to improve the Offline Days and for a scientific publication.
