Re: Input TAB in event description

One way to put tabs in text fields in most things that already use tab to jump between fields is:
1) open your favourite text editor (notepad, whatever)
2) type a tab in the text window
3) highlight and copy the tab
4) paste the tab into the text field where you want it

That worked for me just now in Lightning 1.9 dialog boxes, like in most things.
Not sure exactly what you want the tab to do for you, but you can get it in there.