VB Studio Application Extension Language Switcher Error on Index.html

Summary:

using tutorial https://docs.oracle.com/en/cloud/paas/app-builder-cloud/tutorial-language-switcher/index.html

Trying to put a basic Language Switch option on the Application.

when I set the Action Chain on the button to call a setlanguage function then open url ( set to index.html ), I get the following error.

URL for getting, /fscmUI/redwood/LanguageApp/main/index.html, is not supported.

I tried setting to main-start which reloads the page but the Translation Bundles strings do not change. They do change if I use preferences>Language and set the session language to French or English.

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