You wait for the next update of IPS (4.1.19.1 probably) or you download the first patch (An issue has been identified where certain hooks may stop working on 4.1.19. If you are having problems with some third party plugins or applications, upload this file) mentioned here : https://invisionpower.com/release-notes/4119-r59/ and you apply it via FTP in the same directory mentioned in the link of the patch (system/Theme)
