Google and Microsoft may be mortal enemies, vying over office productivity tools, operating systems, and search engines, but evidence of some cooperation appears in a new version of Google's Web browser.

For people who configured Chrome to use Microsoft's Bing search service, the rough Canary version of the browser shows a customized page when launching a new tab. Instead of displaying Chrome's plain grid of frequently used pages, it shows the lavish photo of Bing's search page.

Chrome-watcher and Google employee Francois Beaufort pointed out the change on Google+ on Tuesday.

Google offers a handful of alternatives for Chrome's default search engine including AOL, Bing, Yahoo, and Ask. At first glance, it might seem sensible for Google to only include its own search service, but the company already has tangled a lot with antitrust authorities about anticompetitive practices.

Financially, search is an immensely important part of a browser: it leads to search results that can carry revenue-generating advertisements. The lion's share of Mozilla's revenue comes when Google shares this revenue derived from searches within the Firefox browser, and Google has declared Chrome "exceptionally profitable" because it doesn't need to share search revenue with others when people search using it.

Microsoft knows the importance of search, too. It's been working for years to compete against Google's dominant service, adding enticements such as Bing search rewards to attract customers.

Google is the top site for search in the US, with 67.5 percent share in March, according to ComScore. The new Bing interface in Chrome points to a Microsoft-hosted page for new Chrome tabs that comes complete with other Bing search-page features: hot spots with information on the image, arrows to cycle to previous images, an "info" button that searches for more information on the subject, and a download button for those who'd like to keep the image as wallpaper.

Canary is a frequently updated version of Chrome that includes many of the latest changes that programmers have added. It's not as well tested as the developer, beta, and stable versions of the browser, though, so be careful if you install it.