Selection Highlighting Settings allows you to change the color, opacity and line thickness of your selected items. By default, the Selection Highlight Color is set to Yellow, but this can be changed to any color you would like by going to the Settings panel and selecting a new color. Same with the Opacity and Line Thickness, each of these can be changed to your preference. This is a per-model setting, which means for each model this will need to be changed to your preference.