Some users probably remember when we first released the new Responsive skin back in 2018. Since then, the responsive skin has been developed further, some improvements were made, and the skin was promoted to be the default skin for new Kolab Now users.
We in the Kolab Now team love the Responsive skin, and we were not going to miss the old static skin when it was not deployed during the update to the latest version of the webclient. We had only received positive feedback about the responsive skin so far, but it turned out that some users still were very fond of the old look and feel.