In December last year Google announced the deprecation of the Google Earth API (also known as the Google Earth Plug-in). It is set to stop working one month from now on December 12th, 2015. The documentation page for the Google Earth API states that it will be shut down on that date.
The reason Google has given for terminating the Google Earth API product is that it is reliant on an ageing technology called NPAPI which is not considered secure and most browsers are dropping support for it or have already done so. In addition, it was never available on mobile platforms.
Google Chrome never included support for NPAPI in its 64-bit version released in September, 2014. The 32-bit version of Chrome gradually dropped support for NPAPI (and with it the Google Earth API) initially making it harder to access in April, 2015, and finally dropping support altogether with the release of Version 45 in October.
We believe Safari still supports it.
It still works in Firefox and we still find many uses for it, such as for finding recent imagery releases. Download this KML file to see the location of imagery in Google Earth that was captured in November (less than 12 days old!).
The Google Earth API has many great uses. We showcased a number of them in this series of posts earlier this year. We at GEB believe Google should consider allowing the GE plugin to continue to work at least until a suitable replacement is in place (with the next version of Google Earth, perhaps?).
My flying skills could use some work. GEFS Online is a popular flight simulator based on the Google Earth API.