If there is a black background on the back of the font when typing, it is usually caused by shading. Just turn off the shadows. Let's give you a brief demonstration.

Computer: MacBook AIr

System: macOS 12

Software: WPS6.0. 1

1. First, we open the WPS document, and we can see that the input text appears on a black background.

2. Then we use the mouse to select all the contents.

3. Click on the character shadow at the top to close it.

4. In this way, there will be no black background when typing, as shown in the figure.