Yn ystod tymor y Senedd hon, hefyd, gwelwyd datblygiadau cyfansoddiadol o bwys, gan gynnwys Deddf Cymru 2017 a chyflwyno trethi datganoledig yng Nghymru, ac mae gan bobl ifanc 16 ac 17 oed a dinasyddion cymwys o dramor hawl bellach i bleidleisio yn etholiadau Senedd Cymru ac etholiadau llywodraeth leol.
This Senedd term has also seen significant constitutional developments, including the Wales Act 2017 and the introduction of devolved taxes in Wales, while 16 and 17-year-olds and qualifying citizens from overseas now have the right to vote in Senedd and local government elections.