I wanted to take a moment to talk about one of the major changes in this release, the removal of the original portal experience. In the September release last year there was a ReportServer catalog setting "UsePortalV2" which, when set to false, would take you back to the previous experience. This has fallback been removed in the January 2022 update, and the new portal is the only experience available. Several factors went into this but the biggest was the deprecation of some underlying technology that the original portal was using.
One of the biggest blockers people reported in the new experience was several new icons had colors which clashed with the brand package being used. We have added new items to the colors.json brand package file to allow theming of these icons in this release. Please find them in the documentation for branding the web portal.
The changelog has been updated with the following information.
Power BI Report Server
Version: 1.13.8054.40631 (Build 15.0.1108.153), Released: January 24, 2022
Original Portal experience for PBIRS has been removed. Previously UsePortalV2 = false in database would enable the original experience, but this has been removed.