Bug 466316

SUMMARY
A recent Kate release changed how one can open multiple sidebars on the same side of the window: in the context menu of a sidebar tab, one can click (Move To) Own Section; one can then move some other sidebars into the new section, and one can open one sidebar from each section. These arrangements are properly saved into sessions when quitting and reopening Kate. However, if I switch between sessions using the Sessions menu, these arrangements are forgotten.

STEPS TO REPRODUCE
1. Have multiple sessions, and open one.
2. Right-click a sidebar tab (icon/label), and click Own Section, and (optionally) open a sidebar in each section.
3. Switch to a different session using the Sessions menu (using Recent Sessions, All Sessions or Manage Sessions...). 
4. Switch back to the previously used session (in which you created sidebar sections) using the Sessions menu.

OBSERVED RESULT
The sidebars on a given side of the window are in a single section again, and only one is open.

EXPECTED RESULT
The sidebars (how they are arranged into sections and which ones are open) are as they were when the session was last used.

SOFTWARE/OS VERSIONS
Operating System: openSUSE Tumbleweed 20230222
KDE Plasma Version: 5.27.0
KDE Frameworks Version: 5.103.0
Qt Version: 5.15.8
Kernel Version: 6.1.8-1-default (64-bit)
Graphics Platform: X11

ADDITIONAL INFORMATION
The workaround, of course, is to avoid switching sessions using the Sessions menu; just quit Kate if you don't need the current session to be open any more, and start it again with the desired session.