Add "highlighter" feature

Hi, please add a "highlighter" feature, in addition to the already included "shading" feature.

John Commented

It has highlighting but I can only figure out how to select one word at a time. It would be nice if I could select whole sentences or paragraphs. To highlight a selected word just hold your finger on it for a second or so and the windows right mouse click menu will pop up and select highlighting from there.