Signout url and fromURI for SAML application

I have a SAML OKTA application, and I am trying to configure things so that it will redirect to a custom url when a user signs out. I cannot set a global default destination url because there are other sites that use this app, and each site needs to be able to redirect to itself when logging out. I’ve seen other forum posts which suggest that sending users to a user like this one should work.

https:/my-okta-url-here.com/login/signout?fromURI=https://my-destination-url-here.com

Is it possible for a SAML OKTA configuration to use the fromURI parameter when logging out? If so, how? It doesn’t seem to be working by default.