Comment # 8 on bug 1092309 from Dominique Leuenberger

This was part of product-builder 1.1.0, which entered Factory on June 2nd 2018

Starting with snapshot 0602. the installer no longer finds the repository on
the DVD when the DVD is 'used as a USB boot medium' (as many users nowadays
copy the DVD on a USB stick, and not on a DVD< this is kinda a common setup)

(of course prod-builder 1.1.0 had more changes, but this one here seems most
probable to have caused the regression)

See openQA failure: https://openqa.opensuse.org/tests/686111#