Learn Hardcore Russian: Во время обсуждения фильма в чате я стараюсь не спорить. - During the discussion of the movie in the chat, I try not to argue.

Во is a phonetic variant of в used to make pronunciation easier, especially before certain consonant clusters.
Время starts with вр-, so во время is the standard, natural-sounding form: во время = during.

What case is обсуждения in, and why?

Обсуждения is genitive singular of обсуждение (discussion).
The preposition-like phrase во время requires the genitive:

во время чего? → обсуждения

So the structure is: во время + Genitive.

Why is фильма in the genitive too?

Because обсуждение is a noun derived from the verb обсуждать (to discuss). With many “action nouns” in Russian, the thing being acted on is commonly put in the genitive:

Verb: обсуждать фильм (Accusative) = to discuss a film
Noun: обсуждение фильма (Genitive) = discussion of a film

So фильма depends on обсуждения: обсуждение (чего?) фильма.

What does в чате mean grammatically, and why that case?

В чате means in the chat (i.e., in a chat room / chat app).
After в meaning location (in), Russian uses the prepositional case:

в (где?) чате → чате is prepositional singular of чат

Why is the word order like this: …в чате я стараюсь…? Could it be different?

Yes, it can be different. Russian word order is flexible and often used for emphasis/topic.

Starting with Во время обсуждения фильма в чате sets the scene first (During the discussion… in the chat…), and then gives the main statement я стараюсь не спорить.

A more “subject-first” variant is also possible, with slightly different emphasis:

Я стараюсь не спорить в чате во время обсуждения фильма.

Both are grammatical; the original sounds natural for “context → main point.”

What tense/aspect is стараюсь, and what does it imply?

Стараюсь is 1st person singular present tense of стараться (imperfective).
It typically expresses a current, repeated, or general habit/effort:

я стараюсь… = I try / I make an effort… (in general or as a typical behavior)

Why is не спорить an infinitive, and why does не go there?

Стараться is commonly followed by an infinitive describing the action you’re trying to do (or avoid):

стараться (что делать?) → не спорить

Negation не normally goes directly before the word it negates—here, the infinitive спорить.

Why спорить (imperfective)? Could it be поспорить?

Спорить is imperfective and suggests arguing as an activity in general (not starting it / not engaging in it).

Поспорить is perfective and often suggests arguing “for a bit” or as a single bounded event. With стараюсь не…, не спорить is the most neutral and common choice for “try not to argue (in general).”

Could I say it with a когда clause instead of во время?

Yes. Во время + Genitive is a compact “during” phrase; a когда clause is more sentence-like:

Когда мы обсуждаем фильм в чате, я стараюсь не спорить.

Both are correct; the когда version can feel a bit more conversational and explicit.

Do we need any commas in this sentence?

No commas are required here because there’s no subordinate clause—just prepositional phrases plus the main clause:

Во время обсуждения фильма в чате (one extended time/place phrase)
я стараюсь не спорить (main clause)