Cannot add proper slur to grace notes when there are more than one.
Create a note, add three grace notes in front. Select all, add slur -> no result. Click on first grace note, add a slur. It connects to only the next note. Shift+right arrow does nothing, dragging does nothing.
If there is only one grace note I can properly connect it to the main note. If there are two, I can connect each other, but not to the main. If there are three, there is no way to do it even vaguely correctly.