Roblox Corp. shares dropped Friday following a report that the social-gaming company’s app in China will be unavailable for an undetermined period after being shut down in December. Roblox RBLX shares ...

Roblox Corp. shares plummeted Wednesday for their worst day since going public, as more “once-stuck inside kids” are going outside and making it harder for the social-gaming platform to make money.

While it doesn’t happen too often, there are times when the central Roblox servers malfunction, have some sort of internal issue, or are simply offline for maintenance. If you’re trying to play a game ...