The ng-tags-input has an important bug regarding regex modifiers. We implemented a custom workaround for version 2.1.1-1, shipped with the extension. There exists a PR on GitHub which still is not merged https://github.com/mbenford/ngTagsInput/issues/278 . When the PR is merged we should update the whole lib and provide CDN, e.g., for 2.1.1-1: INCLUDEJS //cdnjs.cloudflare.com/ajax/libs/ng-tags-input/2.1.1-1/ng-tags-input.min.js