In Bug 259391, I added a "narrow mode" to the inspector, which moves the details sidebar to the bottom. However, on some tabs the sidebar is of very limited usefulness and gets in the way, so it may be desirable to automatically hide it or even devise an alternate UI for narrow mode. This issue is opened per the discussion in the associated PR (https://github.com/WebKit/WebKit/pull/15981#issuecomment-1653436582) for that bug.
<rdar://problem/114301860>