What is the ruling on praying in mosques that have Sharia violations, such as praying too quickly, the Imam being elevated above the worshippers, and celebrating innovated holidays? How can one deal with those who practice these actions? Is it obligatory to establish a new mosque to follow the Sunnah, or is it sufficient to gather and study knowledge?

It is permissible for the imam's place to be slightly elevated above the worshippers, and performing the regular Sunnah prayers at home is better than performing them in the mosque. Collective Dhikr (remembrance of Allah) tied to a specific time is an innovated bid'ah (innovation). The requirement to recite Al-Fatihah is waived for a worshipper whose imam bows before they complete it. Supplicating (making Du'a) in Rukū' (bowing) and Sujūd (prostration) is recommended. Celebrating the Prophet's birthday (Mawlid) is a bid'ah. What has been mentioned does not preclude praying in those mosques. The phrase "good innovation" has already had its legal meaning clarified. It is not legislated to build a new mosque if it leads to the division of the Muslim community. Rather, effort must be exerted in combating innovations and advising their proponents with wisdom. This is alongside the necessity of gaining deep understanding in religion and striving to educate Muslims through beneficial means, such as teaching or distributing useful lectures. One can refer to Fatwa No. 36200 regarding the Friday sermon in the Turkish language.