One shop that I noticed was doing this is csv-direct.de. First visit a product page, e. g.:
https://www.csv-direct.de/artinfo.php?artnr=AGX1428619&KATEG... (758,93€)
then look at the geizhals price:
https://geizhals.de/ubiquiti-unifiswitch-enterprise-24-rackm... (748,09€)
After you have visited the page from geizhals, the lower price will stay even on direct links, for that product only (until you clear local data/cookies).