Hi, please Copy/Paste about:preferences#search to the Address Bar and Enter. Below One Click Search there is a Button Marked : Restore Default Search Engines. https://support.mozilla.org/en-US/kb/add-or-remove-search-engine-firefox

Please let us know if this solved your issue or if need further assistance.

I already said in my initial post that these were not defaults I was trying to restore.

If they are not part of the Firefox installer, you will have to find them yourself.

Hi kohi, Do you have a backup of your Firefox data? If so, go to [=] > Help > Troubleshooting Information, then click on Open Folder. That will open Windows Explorer in your Firefox profile.

If you have a backup of the files in that folder, restore the file search.json.mozlz4

For more information, check out the following article: Recovering important data from an old profile

All installed search engines were stored in the search.json.mozlz4 file in profile folder. It is possible that if you restore a copy of this file that you get back the lost search engines. The search engines are no longer present as individual files like in older Firefox versions in the searchengines folder, but all search engine data is stored in one file named search.json.mozlz4.

Thank you Chris and cor-el, for actually adding helpful replies. That is very good information to know for the future. Unfortunately I hadn't backed up my firefox since the upgrade to quantum, and I found that even my latest backup of old firefox didn't include those engines.

I was really hopeful that restoring them or re-adding them was possible in some way, and I suppose your answer(s) are the closest I could get to doing so. But in my browsing around for more answers I discovered Mycroft Project which had comparable plugins to what I had lost. That leaves me satisfied for now, though I'm hesitant to call this "resolved" because I really would like to find a way to manually add engines, similar to a feature I recently discovered Chrome has.

Can anyone answer why a site with a search feature, which used to be add-able with the little green plus sign, no longer would be? I'm aware a lot of extensions were rendered incompatible with quantum, but I don't suspect that is the same reasoning here, since I was using my engines perfectly fine until my mishap yesterday.

I use an add-on that makes backups of my user profile, Just In Case. Unfortunately, it is not compatible with the current Firefox.

Every now and then, open the profile folder and create a copy of the current profile as is to another location on your hard drive. This way you will have a backup.

If you do this each day, you will not lose much data. This should be done with Firefox Closed.

Note: In case you need to restore from these backups, you may need to overwrite old or corrupted files.

kohi said

Unfortunately I hadn't backed up my firefox since the upgrade to quantum, and I found that even my latest backup of old firefox didn't include those engines.

Let's try "Previous Versions" -- details later in this reply.

...I really would like to find a way to manually add engines, similar to a feature I recently discovered Chrome has.

Can anyone answer why a site with a search feature, which used to be add-able with the little green plus sign, no longer would be? I'm aware a lot of extensions were rendered incompatible with quantum, but I don't suspect that is the same reasoning here, since I was using my engines perfectly fine until my mishap yesterday.

If you have the classic separate search bar on your main toolbar, it should light up with the green + icon when you are on a page containing an OpenSearch plugin tag. Some sites do not add this on all pages but instead give you a link to install their search plugin.

(A way to add a search engine from a page through the ••• menu in the address bar is in the works. I haven't checked recently on when it is going to appear in Firefox.)

To check for older versions of a current file in your profile folder on Windows 7:

Open your current Firefox settings (AKA Firefox profile) folder using any of these methods:

• "3-bar" menu button > "?" Help > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, on the Profile Folder row, click the "Open Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Scroll down to search.json.mozlz4 and right-click > Properties. Then click the Previous Versions tab and wait a few moments for Windows to search recent restore points (typically created at Windows Update time). You can use the "Copy" button to export a file out to a different location.

To inspect the file's contents, you can decompress it using this page:

https://www.jeffersonscher.com/res/searchjson.html

If you click the Save JSON and load it into a Firefox tab, the structured viewer should allow you to see what is in it.

If you decide to replace the live search.json.mozlz4 file with an old one, make sure to exit out of Firefox first to release file locks.

You can use this code in the Browser Console to add a search engine via an XML file stored on your computer. Note that you may have to enable the command line in the console.

• https://developer.mozilla.org/en/Tools/Browser_Console

/* load search engine via local XML file */
var fp = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
fp.init(window,"Open file",Ci.nsIFilePicker.modeOpen);
fp.appendFilters(Ci.nsIFilePicker.filterXML);
fp.open((rv) => {
  if (rv == Ci.nsIFilePicker.returnOK) {
   var path = fp.file.path;
   var url = OS.Path.toFileURI(path);
   Services.search.addEngine(url, null, null, false);
  }
})

cor-el; Thank you, that's roundabout what I was searching for by coming here. You guys have been very helpful and I'll be saving this information for the future.

jscher; I LOVE YOU. This 100% worked. I'll be manually backing up this json file now.

Thanks everybody!!