The phrase "O Gemini disse" (Portuguese for "Gemini Said") also works, but some times it's from someone that is genuinely paraphrasing Gemini responses.

But searching it in English makes everything more evident, since the phrase starts in English and then suddenly changes it to Portuguese.

I found even a digital news website doing it: https://cenariomt.com.br/mato-grosso/gemini-said-rondonopolis-mobiliza-pit-stop-contra-exploracao-sexual-e-trabalho-infantil-no-carnaval/

I wasn't the one that found out about "Gemini said" text being added when you copy the model response, but I decided to google about it to discover more, and ended up finding those kind of results. I tested on my computer, with Firefox and Chromium on Linux and couldn't reproduce this, so I believe this is something related to Chrome or Windows, since my girlfriend discovered it.

My guess is you use the equivalent of "Gemini said" in other languages too, you might find similar results.