You may have set the default theme in the web.xml as follows:
<context-param>
<param-name>primefaces.THEME</param-name>
<param-value>le-frog</param-value>
</context-param>
To get application specific themes to work set the default theme in the web.xml as follows:
<context-param>
<param-name>primefaces.THEME</param-name>
<param-value>#{ivyPrimefacesThemeResolver.getTheme('le-frog')}</param-value>
</context-param>
Also see the [migration notes][1] of Axon.ivy 6.0.1 for more information.
[1]: http://developer.axonivy.com/doc/6.0.1/doc/migrationNotes/MigrationNotesEngine.htmlhttp://developer.axonivy.com/doc/6.0.1/doc/migrationNotes/MigrationNotesEngine.html