In a stock installation of DSL 2.3, double-clicking on image attachements (e.g. image/jpeg) in Sylpheed doesn't work.
I fixed this by editing ~/.sylpheed/sylpheedrc and changing the value of "mime_image_viewer" from
Code Sample
mime_image_viewer=display '%s'
to
Code Sample
mime_image_viewer=xgzv '%s'
(I'm setting up an old laptop as an internet/email machine for my mother who lives in another state, so it has to be bulletproof! So far DSL is looking like the solution...) Good tip, Thanks!
original here.