In a non e10s tab: - Open the inspector - Select a node nested somewhere (not just html, head or body, something nested below that) - Reload the page ==> Observer that the markup-view auto-expands to that node and selects it In an e10s tab: ==> body is always reselected by default

This is controlled by selectionCssSelector and is most likely failing because of the call to _target.url in the getter http://dxr.mozilla.org/mozilla-central/source/browser/devtools/inspector/inspector-panel.js#381

Also, the call a get the CSS selector is not remote safe for the same reason that the "Copy Unique Selector" context menu isn't. See https://bugzilla.mozilla.org/show_bug.cgi?id=967201#c4 for an explanation of how to fix this part

Well, that was easy after all. Uses the new remote getUniqueSelector() method. Try: https://tbpl.mozilla.org/?tree=Try&rev=bad28252a0bc

Comment on attachment 8508932 [details] [diff] [review] Use remote method to get unique selector Review of attachment 8508932 [details] [diff] [review]: ----------------------------------------------------------------- R+ assuming a green try build.

Reproduced the initial issue in Firefox 36 Nightly from 2014-10-21. The issue no longer reproduces in the latest Firefox 38 Nightly (BuildID=20150211222327) on Windows 7 x64, Mac OS X 10.9.5, Ubuntu 12.04 x86.