filter : thumbnails of each step + disable operations after step n

[v1nce]

Could we have thumbnails at the left of each individual step of a filter ?

for operation that need a source object we could use the current object as a reference
(or the last if none is selected
 or a sample one (a transparent rainbow ?) if there is no shape at all
)

This would be really helpfull when you're dealing with complex filters (30+ operations)

Is there possible to add a bypass ? When debugging complex filters, I always add a final feMerge to which I branch the step n. If step n looks ok then I go to the step n+1 and so on. If there are so many operations that the windows has a scrollbar (*) this is really frustating. So is it possible to add a new option that allow to set the selected step to be the last one (all steps after would be greyed out).
eg : add a "stop there" menu item when right clicking a step

(*) my screen is 1200px height but this is not enough for filters