Google Chrome

1. Click the  menu icon in the top right corner of the browser and select "Settings"
2. Open advanced settings
3. Make sure the option "Use hardware acceleration when available" is checked
   
   

Mozilla Firefox

1. Click the  menu icon in the top right corner of the browser and select "Settings"
2. Make sure option "Use recommended performance settings" is unchecked
3. Then make sure "Use hardware acceleration when available" is selected
4. (Optional) If you run more than one game in your browser at once, set "Content process limit" to a higher number