The best replacement for groupbox is panel.

The best alternatives to groupbox are rated as following:
★★★★★  panel
★★★  panel net

Your alternative for groupbox is not listed? Suggest!
Speaking about groupbox, one probably shouldn't forget about radio buttons.

Other search terms related to groupbox and their ratings are:
★★★★★ radio buttons
You have in mind a companion for groupbox and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of groupbox in all years. Click on graph for more.
groupbox
panel
panel net