I tried downloading all the thumbnail plug-ins possible but none show XCursor file previews. In KDE4 Dolphin came preinstalled with Cursor File Previews.
Probably a kio-extras bug/wish/needs porting to the KF5. The cursorthumbnail build is disable in the kio-extras/thumbnail/CMakeLists.txt, line 152..168: https://cgit.kde.org/kio-extras.git/tree/thumbnail/CMakeLists.txt .
*** Bug 400836 has been marked as a duplicate of this bug. ***
*** Bug 412315 has been marked as a duplicate of this bug. ***
Git commit 55d370392efa7d114cca648bde4109453fa760f8 by Kai Uwe Broulik. Committed on 01/01/2020 at 17:21. Pushed by broulik into branch 'master'. Restore cursor thumbnailer Baiscally just find xlib and change the link targets. There's no xcb equivalent for plain cursor file loading. FIXED-IN: 20.04.0 Differential Revision: https://phabricator.kde.org/D24431 M +23 -13 thumbnail/CMakeLists.txt https://commits.kde.org/kio-extras/55d370392efa7d114cca648bde4109453fa760f8