Last Friday I patched the new help of LibreOffice to fix a bug about the correct detection of the operating system passes as &System= in the URL.
It affects the usage of <switch> and <switchinline> with consequences on <case> and <caseinline> as well as the <default> and <defaultinline> inside the help pages (the xhp files).
I had to change the default / defaultinline to an new entity named DEFAULTSYS, shown every time the OS is not specified.
The logic is that is there is a specific usage of &System=, then the page must display the options of the parameter specified by &System=. It must also hide all option of DEFAULTSYS in the page.
If the page has option for <case select='sys'> but the OS passed is not an option of <case>/<caseiniline> then the DEFAULTSYS options must be shown.
For example, the URL pass &System=WIN and the options are for UNIX, then the contents displyed must be DEFAULTSYS.
Patch is: https://cgit.freedesktop.org/libreoffice/help/commit/?id=13098ccef163c813ae3e196511f44a16a6e73fdd