Yes, one of the main results of Firefox's Refresh feature is that most extensions are removed. ([[Refresh Firefox - reset add-ons and settings]]) Do you recall the name so you can install it again? If not, you can try to research it using your old settings folder, which you should find inside an Old Firefox Data folder on your desktop. When clicking through this folder, you should see: * a semi-randomly-named folder, often with "default" in the name * inside that, an extensions folder * inside that, various files and/or folders for your old extensions The challenge is that extension files/folders often are named using unique id's instead of friendly descriptive names. If none seems obviously useful, try this instead: Return to the main level of the old settings folder and find the file '''extensions.json''' and right-click > Copy it. Then right-click > Paste in a blank area of the list. Windows should now show '''extensions - Copy.json'''. You can rename that with a .txt extension to access it more easily using a text editor. In the file, search for any part of the extension's name and you should see information such as the following (example is Adobe Create PDF extension): {"id":"web2pdfextension@web2pdf.'''adobe'''dotcom","syncGUID":"v4hJ7nJBAhrE","location":"winreg-app-global","version":"2.0","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null, "optionsType":null,"aboutURL":null,"iconURL":"chrome://web2pdfextension/skin/C_AdobeLogo_48x48.png","icon64URL":"chrome://web2pdfextension/skin/C_AdobeLogo_64x64.png","defaultLocale":{"name":"Adobe Acrobat - Create PDF","description":"Converts a web page to PDF","creator":"Adobe Systems Incorporated","homepageURL":"http://www.adobe''.''com/"},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files (x86)\\Adobe\\Acrobat 11.0\\Acrobat\\Browser\\WCFirefoxExtn","installDate":1389397098333,"updateDate":1437178060195,"applyBackgroundUpdates":1, "bootstrap":false,"size":286843,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":true, "hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}", "minVersion":"4.0","maxVersion":"*.*"}],"targetPlatforms":[],"multiprocessCompatible":false,"signedState":0} Note: turn on word wrap if necessary, since otherwise it's one long line. If you skim through the parameters, hopefully you can find the full title.