error console message

1
Error: uncaught exception: [Exception... "'[JavaScript Error: "this.$ce is not a function" {file: "file:///home/surf/.mozilla/firefox/ox2zcjs7.default/extensions/%7Be4a8a97b-f2ed-450b-b12d-ee082ba24781%7D/components/greasemonkey.js" line: 364}]' when calling method: [gmIMenuCommand::doCommand]" nsresult: "0x80570021 (NS_ERROR_XPC_JAVASCRIPT_ERROR_WITH_DETAILS)" location: "JS frame :: chrome://browser/content/browser.xul :: oncommand :: line 1" data: yes]