You might have heard about Google’s innovative search feature ‘Search by Image’, which helps you discover all kind of information related to a specific image. There is an official add-on for Firefox and Chrome to make this easier, which adds a right-click menu option to search an image. ‘Google by Image’ is a similar add-on for Firefox.
‘Google by Image’ extension adds a right-click context menu to search an image with Google's new "Search by Image" capability. This restartless add-on is very easy to use, just install and right click on any image and click ‘Google by Image’ to search.
However, it showed problem on some web pages and images. Even on Google image search results, I found error with some images; otherwise, it is a nice add-on.
Interested users can download it at Mozilla add-on site.