One of the new features of Qlik Sense november 2018 is the bundled extensions. If you install the bundle that’s included with the release (and I think you should) you will get a couple of extensions, one of them based on my qsVariable:
Based on, because Qlik has renamed it and made some modifications. Since it has a new name your existing apps that uses qsVariable will continue to do so, you will need to convert them to use the bundled version: You should probably do so, since Qlik will maintain the new version, and test and possibly fix it for new Qlik Sense versions.