I've always liked nosquint, but in the last few versions before the awful 57 and now with the change to a 57+ version, it's very hit or miss. Sometimes settings per individual sites work, sometimes they don't, sometimes the interface comes up off of the menubar button and allows changing settings, but does not accept the settings -- clicking the save or the close buttons do not work and the browser must be rebooted. This behavior seems new to Firefox v.57, which brings a host of broken parts, blechh. It was not broken, now it is, good work.