If you press New Tab button on inactive panel, the new tab is created on the panel but the panel is not activated. In this case quick browsing shortcuts (arrows) and filtering will be applied to the tab of the active panel instead of the new tab. It worked well in the stable, but is broken in master now.
It seems to be solved adding a line (https://invent.kde.org/utilities/krusader/-/merge_requests/91).
A possibly relevant merge request was started @ https://invent.kde.org/utilities/krusader/-/merge_requests/91
Git commit a96bfe0793e9b2d347922ccc1683638a1b116410 by Toni Asensi Esteve. Committed on 08/08/2022 at 22:15. Pushed by asensi into branch 'master'. Activate the inactive panel when its Open a New Tab button is pressed FIXED: [ 457333 ] Regression: panel with the tab created by New Tab button is not activated Revision: https://invent.kde.org/websites/krusader-org/-/merge_requests/91 M +1 -0 krusader/panelmanager.cpp https://invent.kde.org/utilities/krusader/commit/a96bfe0793e9b2d347922ccc1683638a1b116410