Sorry I don't know anything about programming.
but I like Only office.

Can you provide a link to a documentation of any other processor that describes the process of customization for the reference?

the user can choose what items they want to display in the menu. because cut copy paste is easily accessible with a keyboard shortcut, but there are some items that I use often but there is no keyboard shortcut for them. For example: highlight,

Please elaborate on your suggestion. What customization you suggest for the context menu exactly?

After selecting a word (or words) a customized right-click menu would be very practical.