Comment 2 for bug 647838

With any font, once you get small enough, the top of the sh'va in "שְׁ", and the kamatz in "שָׁ", will touch the letters above them. And at some other size, probably even smaller, the two dots in the sh'va will smush together.

So I guess this would be a valid bug report if those two things happen at noticeably larger sizes in Ubuntu than they do in other common UI fonts. At the moment, though, while this is a good summary of a design requirement, it's not really a bug report so long as the available Ubuntu font doesn't cover Hebrew at all.