Now that Yahoo has gained search share from Google thanks to its Firefox deal, the search giant seems to be finally hitting back with moves to get users to switch to Google.

I’ve been checking each week since the deal was announced in November to see if Google would finally do as I expected, try to prompt those using Firefox to change back from Yahoo to Google. Yesterday evening, it finally happened.

When I used Firefox on a Windows 10 Lenovo laptop, I got this message:

You can see up at the top, a message saying: “Get to Google faster. Make Google your default search engine” along with “Sure” and “No thanks” options.

More commonly, there’s a message encouraging Firefox users to change their homepage:

“Come here often? Make Google your home page,” is the message, with “Sure” and “No thanks” options.

I got this message when using Firefox on a Microsoft Surface Pro 3 running Windows 10, a Lenovo desktop running Windows 8.1 and another Search Engine Land editor got it even though his homepage was set to Google Translate.

The messages did not appear for me when using Firefox on the Mac, nor when going to Google with Internet Explorer on a PC (though I did get a long-standing message in a different section of the Google home page encouraging me to download Chrome).

Yesterday, Google also actively called out on Twitter to encourage Firefox users to switch back:

This one's for all the Google Search-loving Firefox fans out there → http://t.co/c3C0D9SC8v pic.twitter.com/ocZAOWTrvf — Google (@google) January 21, 2015

The tweet leads to what appears to be a new page made up for Firefox users, telling them how to change.

This is the same page you get taken to if you choose the “Sure” option that Google suggests when visiting its site, when it asks about changing your search engine. There’s a similar page of instructions for changing your home page:

As I said above, I haven’t noted these types of messages in Internet Explorer. But on Twitter, others have told me they’ve seen them within the past two months or so.

Google does have dedicated pages to encourage IE users to switch either their search engine (see here) or home page (see here). So encouraging switching isn’t new for Google. In fact, all the major search engines have done campaigns like that at different times going back for years.

However, the messages for Firefox users are new — and driven, it would seem, because of the reports that Google has lost search share.

I figured it was inevitable Google would do this, if the Firefox-Yahoo deal really did seem to be having an impact. Even the loss of a little share might be enough to scare investors. Certainly, I’ve taken enough calls from various press outlets wondering if the deal and subsequent share loss meant a big problem for Google.

My response has always been that if Google was worried, it could and would fight back in this type of manner. Now it is, and I suspect it will regain some of that share lost to Yahoo.

I also suspect Yahoo won’t gain much more search share than it has, because with the Firefox deal fully rolled out, it’s effectively hit a high water mark for all that particular channel is likely to produce.