Group the following popular web browsers into open-source vs. proprietary
- Firefox
- Chrome
- Safari
Open-source: 
- Firefox

Proprietary:
- Chrome
- Safari
Complete the following task based on the instruction and optional input provided.### Instruction:
Group the following popular web browsers into open-source vs. proprietary

### Input:
- Firefox
- Chrome
- Safari

### Output:
Open-source: 
- Firefox

Proprietary:
- Chrome
- Safari