I localized an Angular App with the standard Angular localize package. That works perfect and I host my app on firebase. I read the firebase article on how to configure i18n rewrites and implemented it in my firebase.json(https://firebase.google.com/docs/hosting/i18n-rewrites). The french version is loaded when .../fr, russian one for .../ru depending on the language preference of the user's browser and as a default .../en for English. The rewrite also works as expected.
I also want to enable the user to save their preference and that should be possible by setting
document.cookie = "firebase-language-override=fr"
However, it seems like the cookie is completely ignored and firebase still serves whatever the user's preference is.
Any experience or suggestion what I can do about it? Are there other ways to change the firebase rewrite behavior?