The Lock / Logout Widget has several issues: a) The "Leave" button, has the icon of the "Shutdown" action b) In the options the "Shutdown" option is missing c) The symbols are on a non-transparent background Reproducible: Always
Can confirm a) and b) points, the c) point seems not relevant any more. Also icon for 'General' tab in module's settings window could be an empty window icon - same as in 'Task Manager', 'Redshift Control' etc. settings modules
*** This bug has been marked as a duplicate of bug 424426 ***