![javascript - keep getting "? Something is already running on port 3000" when I do npm start on react app - Stack Overflow javascript - keep getting "? Something is already running on port 3000" when I do npm start on react app - Stack Overflow](https://i.stack.imgur.com/nsITN.png)
javascript - keep getting "? Something is already running on port 3000" when I do npm start on react app - Stack Overflow
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Why puma workers constantly hung, and how we fixed by discovering the bug of Ruby v2.5.8 and v2.6.6 | by Yohei Yoshimuta | ITNEXT
![javascript - keep getting "? Something is already running on port 3000" when I do npm start on react app - Stack Overflow javascript - keep getting "? Something is already running on port 3000" when I do npm start on react app - Stack Overflow](https://i.stack.imgur.com/K7wjg.png)