Globally applied display-filter list
Description of the feature
Add a 'global' list of display filters, which apply as if they were prepended to the display-filter list associated with each individual image. + a mechanism in the display filter dialog for switching between editing filters of 'current image' or 'global filters'.
Use cases
When repairing scans, it is useful to be able to show all images with a Gamma filter at a very low setting - ~ 0.100 . This shows hidden debris that will cause problems for filter application. Adding the same display filter to each image becomes quite tedious.
A related use case is cropping. when there is no pigment near the edge of the paper, the edge is often difficult to locate; a low gamma setting makes it much more visible.
Another use case that seems to me obvious is checking whether a batch of images is colorblind-safe.
Probably there is an analogous case with Clip Warning, but I've never had cause to learn what that might be.