Lots of Options, Strong Security & Privacy, Easy, Fast

Strength:
• Open source. If you are not familiar with "open source", it means this app is more secure. Because its code is publicly available for review and contributions on GitHub at https://github.com/quodroc/HumbleNewTabPage/
• Attractive MIT license. This means the software code of this extension code is owned and supported by a friendly not-for-profit community. Instead of a for-profit corporation. https://github.com/quodroc/HumbleNewTabPage/blob/master/LICENSE_MIT.txt
• Available for both Firefox and Chrome
• Easy to customized
• Set a solid background color for new tab
• Settings interface can easily be scale up or down
• Export/Import configuration
• Fast
• Lot more features

Challenge:
• This Firefox add-on was recently updated on February 21st, 2020 :) Which is just a few months back. But the Chrome extension was last updated February 10th, 2019. Which is more than one year ago :(