Firefox: add Google search engine - why no such option in search/address bar?

Question

I wanted to find a way to add Google search engine to Firefox on currently used Linux Mint. I've read e.g. that post How to add search engine using Firefox's address bar?. But when on google.com page, clicking 3-dot on the right of address bar did not show that option (and search bar did not show that magnification with plus icon when google.com was opened. Showed for superuser site by the way, I selected it as search and now it is added and that option is gone).

On https://support.mozilla.org/en-US/kb/add-or-remove-search-engine-firefox it is said:

When you visit a website that offers an OpenSearch search engine, you can add it from the address bar Page actions menu.

Click the Page actions (3-dot) button on the address bar.
Select Add Search Engine from the menu.

I've tried to google the issue and found that how-to, where at the end I clicked on

<a href="#" onclick="window.external.AddSearchProvider('/searchengines/google.xml');return false;">here</a>

on page https://www.linuxmint.com/searchengines/anse.php?sen=Google&c=y#,
where google.xml file below:

<OpenSearchDescription>  
<ShortName>Google</ShortName>
<Description>Google</Description>
<Tags>google</Tags>
<Image height="16" width="16" type="image/vnd.microsoft.icon">http://www.google.com/favicon.ico</Image>
<Url type="text/html" template="http://www.google.com/search?q={searchTerms}"/>
<Url type="application/x-suggestions+json" method="GET" template="http://suggestqueries.google.com/complete/search?output=firefox&q={searchTerms}"/>
</OpenSearchDescription>

So looks like google is using OpenSearch (and the by the way the file is not operating system specific). Why couldn't I add it then from address bar?

Answer 1

Got the same problem.

Alternative way for custom search

For an example Google string: https://www.google.com/search?q=%s Here is a workaround with the plugin: add-custom-search-engine

And here we go:

you have google in the about:preferences#search

Answer 2

The key reason why the option to "Add" the search engine is not available to you from https://www.linuxmint.com/searchengines/anse.php?sen=Google&c=y is because https://www.linuxmint.com/searchengines/google.xml is using a name that either A) already exists in your about:preferences#search or B) is the name of one of the Firefox Default Search Engines - even if you already removed that default search engine.

The reason the other answer works is because the name ("google") differs (in case) from "Google".

Also, search suggestions aren't enabled by default, but can be within the Add custom search engine add-on's advanced section using the value http://suggestqueries.google.com/complete/search?output=firefox&q={searchTerms}