User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0 Build ID: 20180815100249 Steps to reproduce: Started Nightly 63.0 with a new test profile. (Windows and Linux) Opened Add-ons Manager. Selected the Extensions tab. Entered uBlock Origin. Pressed the Enter key to initiate the search. Actual results: No results tab opens and this error appears in the Browser Console. [Show/hide message details.] Error: Required argument triggeringPrincipal missing within loadOneTab tabbrowser.js:1381:13 loadOneTab chrome://browser/content/tabbrowser.js:1381:13 openLinkIn chrome://browser/content/utilityOverlay.js:532:26 initialize/< chrome://mozapps/content/extensions/extensions.js:1881:7 _fireCommand chrome://global/content/bindings/textbox.xml:324:11 _enterSearch chrome://global/content/bindings/textbox.xml:341:11 onxblkeypress chrome://global/content/bindings/textbox.xml:379:11 Expected results: A tab with search results should open.