Language bar remembers the language set to individual applications as long as the process is running. In your case it looks like you have Nynorsk (New Norwegian) as your default language but you also have English keyboard layout installed.
At some point you have changed the input language in Messenger to English, so as long as Messenger process is running the input language is switched to the last used i.e. English every time Messenger has focus, being the active window.
If you have Nynorsk as your default input language, this small issue should fix itself when closing Messenger (completely exit it) and re-launching it.
Shortly: the chosen input language in an application resets to default only when application is closed. Otherwise the application uses the last used input language. Read more here