How to use custom ThemeSelector instead of default one in Keycloak 16?

Hello,
Could anyone advise how to enforce Keycloak to use custom ThemeSelector instead of default one with Keycloak 16?
I have created my ThemeSelectorProvider and ThemeSelectorProviderFactory, packaged them into jar and deployed to Keycloak into /providers folder (everything according to documentation here). I see in Server info - Providers, that my ProviderFactory is present - but together with default one. Also, I see in logs, that Keycloak anyway uses default components (DefaultThemeManager - DefaultThemeProviderFactory - DefaultThemeProvider). As a result, when I am redirected to login page (with default theme, no themes configured in Admin interface), Keycloak just uses DefaultThemeProvider. Even after my changes to standalone.xml - I have added SPI like

my-theme-selector-provider


no changes, Keycloak uses default provider.
Could anyone advise - how to get rid of default ThemeSelectorProvider ?