On the CCMS.next interface, if you are viewing revisions of a CSP map and accidentally click on "Rendered Diff", nothing appears in the rendered view (as expected) but there is no way to cancel the rendering view. Until this cancellation occurs, the user is stuck because all the buttons on the Diff view are grayed out. Normally, I would click on one of the other tabs, for example "XML Editing" or "Properties", etc. and then switch back to find the rendering process cancelled but switching back and forth does not do anything in this case. If there is a way to return to viewing diffs from this point, I can't find it so it is at the very least non-obvious.
Created attachment 777146 [details] Screenshot of the described problem Adding a screenshot to illustrate the problem.
Since Content Specs have their own editor now, this really isn't a problem anymore so I'm marking this as won't fix. I also have a very high suspicion that the cause of this is the same as BZ#1006123