Online and also in messages from my French friend I see the indicative used where according to what I’ve learned it would technically be the subjunctive. Is it not used in informal settings?
Like I’ve seen “Je suis content que tu l’as aimé” instead of “tu l’aies aimé”.
Personnellement je dis :
Je suis content que tu l’aies aimé.
Je n'ai pas souvenir d'avoir entendu dans mon entourage quelqu'un utiliser l'indicatif dans ce genre de phrase. Mais, bien que Français, je ne suis pas forcement représentatif.
Toto has answered your question accurately, here I would like to go further and say that not only subjunctive actually is used in informal contexts, but in those situations it is even overused.
The most common situation is after the locution après que: e.g.,
Après que je sois parti...
is incorrect but extremely widespread.
The correct wording is:
Après que je suis parti...
which, I have to admit, sounds very odd, even to my native ears.
In English the subjunctive is pretty much optional, but if you don't use it in French you sound like you are 5. What is not commonly used in French is the past version, similar to subjunctive itself in English: grammatically the right thing to say but seldom used in practice.
In some part of the world, like Quebec, subjunctive is going out of usage. As an example, Radio-Canada, the national broadcaster, has everybody use the indicative (in French). If you listen carefully, you can hear the journalists grind their teeth as they now have to say "... de s'assurer que les devoirs sont faits", discussing education reform, as opposed to "... que les devoirs soient faits".
Most secondary school dropped subjunctive, but fancy/private high schools still teach present subjunctive.
