In bug 585601 we discovered that the following XUL: <splitter disabled="true" collapse="after"><grippy/></splitter> creates a splitter that can be collapsed but not resized. However the problem is that the resize cursor still appears on the splitter. If disabling splitters makes sense for any other reason, then they obviously would not want a resize cursor either.
Created attachment 468150 [details] [diff] [review] Proposed patch
Comment on attachment 468150 [details] [diff] [review] Proposed patch Seeking approval for this trivial theme enhancement.
Pushed changeset 345438665f24 to mozilla-central.