It is an excellent alternative to TechSmith Snagit extension, Screengrab or Awesome Screenshot.
You can use this tool to capture the whole web page from the web browser or just the part which you need.
It comes with a user-friendly interface (the design of this software). There are many amazing editing features.
The great feature of this easy-to-use editor is the editing tools. you can use it to add various patterns, text, arrows and lines to your screenshot.
You can create your own drawing, paste different patterns, text boxes and blur parts of your screenshot that you want hidden.
Not forgetting you can also resize and crop your screenshot.
Then you can save your screenshots in JPG, PNG, BMP format into your hard drive or Google Drive as well.
Finally you can upload your screenshots to be shared.
There are three (3) ways to capture your screen with Nimbus Screen Capture:
i) With the help of the button in your address bar
ii) With the help of the context menu
iii) With the help of a hot key that you yourself assign in the program settings.
This free tool can be use it for Firefox, Chrome, Opera, Android and Windows.
If you want it, you can download the Nimbus Screen Capture here.