Here is the proposed dialog layout from bug 271916.
The dialog layout has these options: Font, Size, Strikethrough, Underline, Italic, Bold, Highlight. These are all standard KDE options with the exception of Highlight. The Highlight button I made in Gimp, but you can see I used a lower "h" instead of upper "H". I can redo the icon with an upper "H" if you want to use it as I do not think that Gnome / KDE have a dedicated Highlight icon.
Here is the proposed dialog layout from bug 271916.
The dialog layout has these options: Font, Size, Strikethrough, Underline, Italic, Bold, Highlight. These are all standard KDE options with the exception of Highlight. The Highlight button I made in Gimp, but you can see I used a lower "h" instead of upper "H". I can redo the icon with an upper "H" if you want to use it as I do not think that Gnome / KDE have a dedicated Highlight icon.