If I have a TAdvRichText editor using a TAdvRichEditorFormatToolbar or a standard action for it, the selection works differently if the word being selected ends in a comma for example.
If I double click the word "time" in this sentence that ends in a comma:
Now is the time,
and then select to Bold it from the toolbar, it correctly sets it to bold. However, you cannot do the same thing to remove bold. You have to manually drag the mouse to select the word "time" in order to be able to remove the bold. You will also notice that double clicking the word when bolded does not highlight the bold toolbar button.