I'm experiencing the same problem on Nobara KDE Linux, but with the GoG-Store-link instead. Clicking on the GoG-store always refers to the Epic-Store webpage. On my laptop with TuxedoOS (Ubuntu 20.04 + Budgie) I don't have that issue. Both are updated to Heroic version 2.10.0. --- Was able to fix it by manually adjusting the last-URL for the GoG-store through debug as per your instructions (@arieljuod). Resetting cache did not resolve it.