Arora was a cross-platform web browser built using WebKit and Qt 4. It had a simple light-weight user interface. It was more of a show-case for the Qt framework than a end-user product. It could be used as a regular browser and it did have features like tabs, history, bookmarks and custom user-CSS. It has not been developed or maintained in decades.
The source code is still available at https://github.com/arora/arora - however, nobody has touched in a decade. Compiling it against a modern Qt version will require a lot of effort.
See Comparison of Web Browsers for current actually updated web browsers.