Some Google (GOOG) users have reported that they’ve been seeing black links instead of the familiar blue links in the company’s search results. The Telegraph, as well as The Next Web, were able to see the black links by opening a private Google Chrome window, among other tricks. However, it appears to be in testing and it’s unknown how many users have so far tried it out.

Regardless, the change would be a significant one, if Google ends up changing the color of its search results links to black. The company has long used shades of blue for its search results. Under those results, Google displays the full link to the search result in green.

While it might not seem like a major change, the Internet has blown up over the test. Reddit users have posted to the forum site all kinds of complaints about the changeover, and Twitter (TWTR) has once again become the go-to place to find troubled users, with one calling the new look “terrible.” Another decided to chastise Google, saying “Bad Google.”

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That reaction is likely what Google would be analyzing as it tests the new color. Ultimately, the company will need to decide whether to stick with blue, change it up a bit, or go with something radically different like black. Early votes from those who have seen the test seem to suggest black might not be the best option.

However, the test highlights how important color is in Google’s appeal. In 2014, for instance, The Guardian reported that Google had made an extra $200 million in advertising revenue just by changing the shade of blue it used in ads in both Gmail and Google Search. The shade change came after a long analysis of data and user reactions.

“We ran ‘1%’ experiments, showing 1% of users one blue, and another experiment showing 1% another blue,” Dan Cobley, then Google’s UK Managing Director, told The Guardian at the time. “And actually, to make sure we covered all our bases, we ran forty other experiments showing all the shades of blue you could possibly imagine. And we saw which shades of blue people liked the most, demonstrated by how much they clicked on them. As a result we learned that a slightly purpler shade of blue was more conducive to clicking than a slightly greener shade of blue, and gee whizz, we made a decision.”

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It’s unclear how widespread Google’s test are for black search results, but given its past analysis of shades of blue, it’s likely in its early stages of deciding whether it’s time to shake things up.

Google did not immediately respond to a request for comment.