Click on the Screen Mask button.

A tint will be applied to the screen.

To change the tint, click on Screen Masking Options.

A window will appear.

Click on the dropdown menu to see the tinting options,

The line you are typing on can be tinted.

The window you are typing in can be left without a tint.

The line you are typing on can be left without a tint.

A tinted line can appear under the place you are working on.

A tinted line can be placed under the mouse pointer.

Use the bottom slider to change the line thickness.

Use the top slider to change the strength of the colour.

Click on the colour block to change the tint colour.

Choose a colour.

Click OK.

Click OK in the Screen Masking Options window to apply the colour.