Expects:

Plugin buttons should be enabled

1. if selection or cursor position is available for creating mgnl link, and
2. if mgnl link is selected (`selected` means placing the cursor on the link or selecting the text containing the link)
   1. Asset link is selected, the Link to Pages button must be disabled
   2. and vice versa, PAGE link is selected, the Link to Assets button must be disabled

Actuals: 2 buttons are enable no matter which link is selected