That's just my impression from browsing through Leabhar Mór Bhriathra na Gaeilge, at least. Also, Ulster uses synthetic forms for muid in the Conditional, according to that (Connacht doesn't) where as Connacht uses it for siad (whereas Ulster doesn't)
The answer it gave me was leas but I have never seen that word before and it is not listed as an alternate when you hover over I or read. Why does Duolingo pop up words that you have not seen previously. BTW, this was in the strengthening exercise, not a lesson.
It's like Spanish, where the pronoun is subsumed into the verb. léim = léann mé
So is it just the first person (leim, leimid) that has a special conjugation, and everything else is leann [whoever]?