STEPS TO REPRODUCE: 1) Load the following testcase: data:text/html,<script>var e = document.documentElement; e.appendChild(document.createElement("svg")); e.appendChild(document.createElementNS("http://www.w3.org/2000/svg", "svg"))</script> 2) Try to tell, in the inspector, which namespaces those elements are in. EXPECTED RESULTS: Have a way to tell that so you know why one works and the other doesn't. ACTUAL RESULTS: No way to tell.

True, there's no obvious way to find this information out. There is a not-so-hard way though: - right click on the node - select "Show DOM Properties" - in the object view that appears below, either scroll to namespaceURI or use the search field at the top (much faster). Bug 704094 aimed at adding this as a sidebar panel directly. This would make it more discoverable and would save a click too.

Sadly, that doesn't work reliably: <script> var el = document.createElementNS("foo", "bar"); Object.defineProperty(el, "namespaceURI", { value: "evil" }); document.documentElement.appendChild(el); </script> that shows "evil" under "Show DOM properties", whereas the string I'm after is "foo".

Bug triage (filter on CLIMBING SHOES).