I am using jqwidgets for a couple of years now in Java projects without problems. I have used it with Tomcat 7 in the beginning and Tomcat 8 later. I have tested a project that runs on a Tomcat 8 on a Tomcat 9. Tomcat 9 in standard configuration combined with the newest Firefox generates an error in the browser console “SyntaxError: invalid range in character class” in the file jqxdata.export.js. I have tested this behaviour also with an old portable firefox and also got this message. Same application on Tomcat 8 works fine.
I have then switched the file and have used the version from the src download, so not minified. I get another error with this: “illegal character” – that seems to be because there is an invisible character before the comment /* tslint:disable */ in line 8. When I delete this character, I get the “invalid range in character class” error again. Unfortunately the browser does not give me a line where this occurs, but I have narrowed it down to the code block that starts in line 3559 and ends in line 3911. When I comment out this section the error is gone and since I have never used the pdf export with jqx that workaround is okay for me right now, but I really wanted to share my findings with you, maybe you can make sense of it and find the cause.
The bigger problem is, when you include the jqx-all.js, you also get the error and then nothing works.