Refresh/reload the lister viewer pane

Somewhere I thought I saw there's a way of doing this, but I can't find it in the manual. Does anyone know how to do this? Wanting to do this from a script. Thanks.

If you are using dual pane this may help: Viewer pane - automaticaly reresh when changing pane

Not sure it's possible in single pane without closing/reopening viewer pane.

Show VIEWPANECMD=clear then Show VIEWPANECMD="open,C:\...\Filepath.jpg"

(Or toggle the viewer pane itself off and back on, which might be easier.)

Thanks, Chuck and Leo.