Fresh AEM Forms SP 6.5.13 installation with "ERROR - This language feature is only supported for ECMASCRIPT6 mode or better: let declaration." in error.log

[LYUAN]

Hi All, 

With a fresh AEM Forms SP 6.5.13 install using Java 11 on Windows, I am getting a lot of "ERROR - This language feature is only supported for ECMASCRIPT6 mode or better: let declaration." in error.log with out-of-the-box client library.

What can I do to prevent the errors from happening?  I've tried clearing cache and recompiling all client libraries but nothing worked.  The compilation errors from the Client Library Manager minimization is bit concerning as the work I am doing is part of a corporate wide server rollout.

One of the error example: 

16.06.2022 16:16:25.277 *ERROR* [[0:0:0:0:0:0:0:1] [1655417784728] GET /libs/fd/flamingo/clientlibs/flamingodialog.min.js HTTP/1.1] com.google.javascript.jscomp /libs/fd/flamingo/clientlibs/flamingodialog/js/flamingodialog.js:158: ERROR - This language feature is only supported for ECMASCRIPT6 mode or better: let declaration.
let propName;
^

The instance was installed with following steps with the latest Oracle Java 11 downloaded from Adobe file share:

1.  java -jar <AEM Quickstart Jar>-p4502.jar -unpack

2.  java -jar <AEM Quickstart Jar>-p4502.jar -r author,nosamplecontent -gui

3.  Deploy SP 6.5.13 and SP 6.5.13 Forms-Addon 

4.  Shutdown the instance with "Ctrl+C" after confirm installation completed in error.log 

5.  java -jar <AEM Quickstart Jar>-p4502.jar -r author,nosamplecontent -gui

6.  Observes error.log to confirm there are no major issues. 

Expected:

at 6.  error.log are mostly clean except during service pack and upgrade deployment 

Actual:

at 6.  various client library compilation errors occurred in the error.log. 

Thanks in advance for all the answers and/or hints.

[SantoshSai]

Hi @LYUAN ,

Please check if this helps: https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/ecmascript6-error-while-bu...

Regards,

Santosh

[LYUAN]

Hi @SantoshSai,

Good reference.  Thanks a lot!

It seems the failing code is coming from OOTB AEM SP 6.5.13.  Is there a way to tweak the Client Library Manager with a compiler that works with ECMASCRIPT6+?

Thanks again,

Scott Yuan

[SantoshSai · Accepted solution]

@LYUAN Let me send you one more similar reference for this: https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/using-es6-function-not-wor...

[LYUAN]

@SantoshSai , thanks for the other references.  I really appreciated it.