Since WildFly 14 i18n ResourceBundle properties file not found if without locale -------------------------------------------------------------------------------- Key: WFLY-11234 URL: https://issues.jboss.org/browse/WFLY-11234 Project: WildFly Issue Type: Bug Affects Versions: 14.0.1.Final Environment: Ubuntu 18.04, OpenJDK 8 and 11 Reporter: Anton Pussep Assignee: Brian Stansberry Priority: Major Fix For: 15.0.0.Alpha1 As discussed in this thread https://developer.jboss.org/message/985930 my i18n properties have not been resolved on WildFly 14.0.1.Final - it was working fine through WildFly 10-13, however. I could solve the issue by renaming my properties file from messages.properties to messages_en.properties. Since this solved the issue, I suspect that WildFly 14 does not accept filenames without locale anymore. Since I'm not sure if this is by design, I'm posting this as a bug report here.