Mihajlović was initially a member of the It's Enough – Restart (Dosta je bilo, DJB) association, better known in English by the name "Enough Is Enough," of which he was the leader from April to November 2018.
Born into a mining family,[1] Mihajlović has a doctorate in technical science and worked for thirty-nine years at RTB Bor, where he was a manager and oversaw planning and production analysis.
He was dismissed from the company in 2015 after making a series of critical posts about its ownership on social media; after receiving a notice of termination, he sarcastically thanked his former employers for demonstrating that he and they had nothing in common.
[8][9] Mihajlović later said that the members who had resigned did so to prevent the DJB leadership from launching serious personal attacks against them; he added that he did not begrudge them their decisions.
[10] Mihajlović initially sought to remain as DJB leader after leaving its assembly group, but he was dismissed by a vote of its main board.