Google announced in 2013 a plan to remove the Netscape Plug-in API (NPAPI) support in Chrome. This change improves Chrome's security, speed, stability, and reduces complexity in the code base. With the release of Chrome 40, Google will no longer allow certain NPAPI plug-ins to run without requiring users approval. As a result, people using Google Talk on Chrome 40 will see a "Plug-in blocked" notification in their browser bar. A one-time approval is required for the Talk service, specifically audio calls, to function. If approval is not granted, users will be prompted to run the plug-in within the Talk UI when attempted to make or receive calls.
When Chrome 41 is released in March, the approval will be required every time the browser is loaded. With the release of Chrome 42 in April, NPAPI support will be disabled by default in Chrome. Audio calls in Talk will then start operating through Google Hangouts and will require Google Voice to be enabled for standard telephone calls.
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