STR: 1. Create new Nightly profile 2. Visit https://bugzilla.mozilla.org/ so that it would be saved in history 3. Type "b" in addressbar [you'll be suggested to go to bugzilla.mozilla.org] 4. Delete the selected part "ugzilla.mozilla.org" with BackSpace(!) 5. Press Enter RESULT: Nothing happened EXPECTATIONS: Page with search results with query "b" should show up. NOTES: 1. If I press Spacebar after step 5, then the page with search results actually loads. 2. The same happens if I set "b" keyword to search with Bing: I can't go to search homepage in Step 5. Note 1 solves this case as well.

Nice catch arni, deleting the selected part with the delete button works fine, but backspace also has the right to do that I think :p Reproduced on windows 7 (32bit) latest nightly 42.0a1 Build ID 20150726030217 User Agent Mozilla/5.0 (Windows NT 6.1; rv:42.0) Gecko/20100101 Firefox/42.0