Do language based redirects take into account browser's language?

Do I understand this correctly. Browser redirects only work if the user has one single value set in Accept-Language?

I have Accept-Language: en-US,en;q=0.5 in my browser and the redirect to the English site doesn’t work. That seems more like a bug.

The settings:

[[redirects]]
from = "/"
to = "/en/"
status = 302
force = true
conditions = {Language = ["en"]}

According to the docs this should work / redirect to the English site.