Iran holds a parliamentary election on Friday seen as a test of the clerical establishment's popularity at a time of growing dissent over an array of political, social and economic crises. The vote will be the first formal gauge of public opinion after anti-government protests in 2022-23 spiralled into some of the worst political turmoil since the 1979 Islamic Revolution. Critics from inside and outside the ruling elite, including politicians and former lawmakers, say the legitimacy of Iran's theocratic system could be at stake due to economic struggles and a lack of electoral options for a mostly young population chafing at political and social restrictions.