With a VNC connection viewed in fullscreen mode, connected to a host that has a larger display, using trackpad scrolling (and I presume also mouse-wheel scrolling, but didn't test) anywhere inside the viewport both sends the scroll events to the host *and* causes the viewport to pan. This makes it very unwieldy to use, under those circumstances. Compare to RDP, where Krdc only sends the scroll events to the host (the viewport stays put). Tested with version 20.12.0.
A possibly relevant merge request was started @ https://invent.kde.org/network/krdc/-/merge_requests/9
Git commit ac72c76de7b85fcebe08af37079048527372e04e by Albert Astals Cid. Committed on 20/02/2021 at 10:19. Pushed by aacid into branch 'master'. VNC: accept the wheel event otherwise wheeling is both sent to vnc and to the outer scrollview which is a bit weird M +2 -0 vnc/vncview.cpp https://invent.kde.org/network/krdc/commit/ac72c76de7b85fcebe08af37079048527372e04e
Git commit d66ffeff28e5789d3085fbb50dbdabaa918c104b by Albert Astals Cid. Committed on 20/02/2021 at 10:22. Pushed by aacid into branch 'release/20.12'. VNC: accept the wheel event otherwise wheeling is both sent to vnc and to the outer scrollview which is a bit weird (cherry picked from commit ac72c76de7b85fcebe08af37079048527372e04e) M +2 -0 vnc/vncview.cpp https://invent.kde.org/network/krdc/commit/d66ffeff28e5789d3085fbb50dbdabaa918c104b