Compare document only allows selecting the second file on disk. It is often inconvenient, for example when files have been received by email and stored temporarily in *\AppData\Local\Temp. Even if I remember this location, it is not possible to open it as this location is hidden by default. My proposal is to give an option to compare to 'recent file', in the same manner as the 'open recent file' dialog does.
OK, had to think about what was being requested. It would be to pick the file to compare from user profile recents. Use case makes sense. --Online Help-- https://help.libreoffice.org/7.0/en-US/text/shared/01/02240000.html?&DbPAR=WRITER&System=WIN The Edit -> Track Changes -> Compare Document uses os/DE default file manager, calling the filedlghelper() flaged for InsertCompare Probably not an easy hack as the File Dialog Helper is not plumbed for it. But seems it should be possible to alternatively direct the file selection for the document compare to the user's profile 'HistoryInfo' holding a users 'Recent Documents' list, as accessed now for opening via the File menu, or via the StartCenter--may be able to reuse that. =ref-= looks like work on bug 95992 touched a lot of this to get the os/DE file dialogs labeled correctly for compare or merge documents. New work of course to point at the user profile... https://gerrit.libreoffice.org/c/core/+/35285
Likewise Open and Recent Documents have two menu entries we would have to add a new UNO command. No objection to this from my side.
as an enhancement request, it makes sense. Maybe an option would be to add a submenu to Compare Documents with two options, from file, from recent files