I normally dock the Styles & Formatting panel on top of the Navigator panel along the right side of the window. As of release 4.4.0.1, it looks like the Styles & Formatting panel is now using the sidebar instead. Now when I dock it above the Navigator window and restart the program, the sidebar will be positioned beside the Navigator panel instead of above it. I'm marking this major because it's a major irritant to have a regression in the UI like this. Of course, if bug 67230, which is almost a year and a half old, would get fixed then two panels wouldn't be needed as much and this wouldn't be such a big useability issue, but having two panels side-by-side takes up a lot of screen space.
*** Bug 87689 has been marked as a duplicate of this bug. ***
"Now when I dock it above the Navigator window and restart the program, the sidebar will be positioned beside the Navigator panel instead of above it." Could you please give more information about the different steps to reproduce it. I am unfortunately still unsure what I have to do. Thank you very much in advance.
I found the solution. The problem seems to be in the old registrymodifications.xcu file under the libreoffice/4/user directory. I created a new profile and then replaced the registrymodifications.xcu file in the old profile with the new file. The sidebar and panels now stay vertically docked the way I positioned them before closing the application.