Error "The use of a keyword for an identifier is invalid" appear

Ionic Framework ionic-v3
1

When I execute ionic serve --c the error below keep appear in my project. I am wondering what problem am I facing? How to trace it?

1 634075 warn DEPRECATION WARNING: ‘dequeueTask’ is no longer supported and will be removed in next major
emoveTask/removeRepeatingTask/removeMicroTask
2 634184 group EXCEPTION: SyntaxError: The use of a keyword for an identifier is invalid
8 634200 error EXCEPTION: SyntaxError: Expected ‘;’
3 634184 error EXCEPTION: SyntaxError: The use of a keyword for an identifier is invalid
9 634200 error STACKTRACE:
4 634185 error STACKTRACE:
11 634202 groupEnd
5 634186 error SyntaxError: The use of a keyword for an identifier is invalid
at evalExpression (http://localhost:8100/build/js/app.bundle.js:5213:6)
at TemplateCompiler.prototype._createViewFactoryRuntime (http://localhost:8100/build/js/app.bundle.js:35708:14)
However, the project still working well.
Anybody can advise?

2

Hey there! So that is something from either Angular2 or one of the polyfils we’re using.

At the moment, it’s just a warning, so need to worry about it.
This will be taken care of and fixed in future releases