Montana’s first-in-the-nation law banning the video-sharing app TikTok in the state was blocked Thursday, one month before it was set to take effect, by a federal judge who called the measure unconstitutional. The ruling delivered a temporary win for the social media company that has argued Montana’s Republican-controlled Legislature went “completely overboard” in trying to regulate the app. A final ruling will come at a later date after the legal challenge moves through the courts. US District Judge Donald Molloy said the ban “oversteps state power and infringes on the Constitutional right of users and businesses” while singling out the...