In an ortho view with the world or view-specific Cplanes active, right mouse dragging pans the view. This has become second nature to me as a user.
Things work that way, as expected, in a Top view ortho to a Custom Cplane. But otherwise when a view is ortho to a custom Cplane, right mouse dragging orbits into a 3d view. Only Shift-rightmouse-drag will purely pan. This makes it very difficult to navigate and maintain an ortho cplane view. One must constantly overraide long-established muscle memory to pan, and reset the cplane view every time this is forgotten. I believe the pan control in a view ortho to a custom cplane should behave as it does in any ortho view of a World Cplane.
Maybe there’s some sort of custom-cplane-ortho-view-RMB-pan-negating setting I’ve inadvertently activated, and I can deactivate it.
There could be a switch for this but it never was considered by McNeel. I found navigating the perspective view troublesome when using a stylus instead of a mouse. The best I could come up with was assign pan to a hotkey or have the pan icon on a middle mouse button popup.
But you say you want to pan in ortho views than I think the plan command should work?
There are a few ways to help though not automatic and don’t pan perspective like you may want.
Make sure always pan parallel views is set in options.
You can in viewport properties set the projection to parallel.
You can use the '_Plan command to set Plan view of CPlane.
There is a subtle difference in setting a tilted custom cplane setting the projection in viewport properties may look like your top view and allow right mouse panning or may look weirdly tilted depending on your custom cplane/ortho view. Plan view will give the ortho of the custom cplan and allow right mouse panning.
do you have Always pan parallel views checked in the options view?
as long as you are in an ortho view this should work. otherwise you might have to change to parallel view but since orthos are always parallel they should always pan with that option, if not they are not real ortho views and you would have to make them parallel first.
to rotate the camera in these you would have to press ctrl shift additionally (at least for windows i guess for mac its cmd shift).