Suppose I'm using the Style sidebar in hierarchical mode. If I: 1. Expand a hierarchy item (which is not my current style) 2. Switch to another kind of style on the side-bar (e.g. from Paragraph to Character) 3. Switch back to the original kind of style on the side-bar the item I had expanded is collapsed again. I believe the default should be a _persistence_ of the expand/collapsed state. Resetting this should occur either never; or on closing and reopening the document; or when switching from hierarchical mode to another mode.
I confirm the described problem with Version: 7.1.3.1 (x64) / LibreOffice Community Build ID: fa76d07d7006a0e2866c3247cef2d5eb55ae8369 CPU threads: 4; OS: Windows 10.0 Build 19042; UI render: Skia/Raster; VCL: win Locale: de-DE (de_DE); UI: en-GB Calc: CL