In the Web Settings tab in JCP, the sub tab: Temporary Internet Files has a field: "Set the amount of disk space for storing temporary files".
When using keyboard to change this, we see that it takes a very long time to decrease and increase.

One method to fix this would be to reduce by 100 mb for each down/up key and use the edit text field to type a specific number.

Another method would be to remove the slider completely. Usability wise it does not serve any purpose.