Google's prototype Chrome OS laptops do not yet support Java, and support for Flash Player 10.1 is being called a "work in progress".

Early testers of Google's Chrome OS may see error messages stating that the browser is missing a plug-in, or that Java is not installed when they attempt to use Java-based applications: for example, video games that run in the browser. Attempting to download and install Java may not solve the problem because the Cr-48 prototype running Chrome OS can only read a few basic types of files.

"At this point we only support a limited number of plug-ins and Java is currently not supported," a Google spokesperson confirmed.

Google has started shipping prototype versions of the forthcoming Chrome OS laptops to beta testers, in an effort to work out the bugs before general availability. Commercially available Chrome OS netbooks will be sold by Acer and Samsung in mid-2011, giving Google plenty of time to add support for Java and improve compatibility with Flash.

In addition to the aforementioned issue with Java, Chrome OS beta testers may also see Adobe Flash content break from time to time.

Adobe engineering senior director Paul Betlem provided an update in a blog last week.

"In terms of Chrome laptops specifically, as with many aspects of the device, Flash Player 10.1 support remains a work in progress," Betlem said.

"Video performance in particular is the primary area for improvement, and we are actively working with the engineers at Google to address this. Enabling video acceleration will deliver a more seamless experience on these devices. Because Flash Player is integrated directly into Chrome laptops, users will automatically benefit from the latest features and improvements as new versions of the software are pushed out.

"The work we're doing on acceleration for video in Flash Player is a top priority because the vast majority of video on the web is delivered using Flash."

Chrome OS is a Linux-based desktop operating system designed to run Google Chrome, requiring users to do all of their work and play within the browser. The prototypes sent out to beta testers have some way to go before they are ready to be sold in shops.

While the machines provide a fast startup and a security model that does not require antivirus software, so far they provide only limited support for USB devices and SD cards. Although Google is designing the device to work exclusively with web applications, many or most consumers would want access to removable storage to manage music devices and pictures. Separately, Apple is likely to offer a cloud-based version of iTunes at some point, perhaps making USB support unnecessary for some users.

Google is also working on providing offline access to Google Docs, and says it will be available early in 2011.

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