The code is running nicely but I dont't understand where am I get this error.

It says:

VM428:7 Uncaught TypeError: Cannot read properties of null (reading 'CodeMirror')
    at <anonymous>:7:17

Any sort of help with this will be appreciated.

Thanks in advance.

CodePudding user response：

Remove blackbox extension and react development tool extension from chrome

CodePudding user response：

Extensions : Remove blackbox extension and react development tool extension from chrome

CodePudding user response：

Just Remove blackbox extension from your chrome and its done