DM: Anyway, the looping "meditations" on the speakers are abruptly cut off and replaced with a live mic feed.
Starlight Glimmer: Oh, good morning!
DM: The door finally opens and Starlight Glimmer is standing there with a knowing smile. It seems like the entire town is gathered in the street behind her.
Starlight Glimmer: I trust you had a /pleasant/ night?
Twilight Sparkle, Rarity, Rainbow Dash, Applejack, & Pinkie Pie: *No!*
Starlight Glimmer: Well! Maybe we can fix that. This way, please. There are some *friends* who would like to see you.
Fluttershy: So... moment of truth?
Twilight Sparkle: Moment of truth!
Rarity: We'll help sell it in every way we can, darling.
Applejack: Yup! She won't even suspect a thing.
Rainbow Dash: Worst-case scenario, I'll just punch somebody as a distraction!
Pinkie Pie: It's a good thing Starlight can't hear us give all these out-of-character affirmations!
In the context of the world of a tabletop game, player-to-player communication might be the most strange, eldritch power the party has at their disposal.
When my players talked about their plan of action ... Usually something shady like 'So, do we burn the wizard tower?', 'Can someone pickpocket the Wizard?', 'Should we wait the night to try to kill the Wizard while he sleep?' I let them talk a few second before saying in character 'You know I'm next to you and I can hear you?' and join the conversation.
Player 1 : Let's kill the Wizard while he sleep.
Player 2 : No, destroying his tower is better, who knows he he hasn't safeguard to prevent assassination when he sleeps.
Player 3 : But no tower, no loot !
Me (as wizard) : And yes, I would like to keep my tower too, it's where I keep my stuff. I don't understand why you talk about that in front of me?
P1 2 & 3 : No, we are talking together, not to him.
Me : But he is next to you. So unless you have a telephathy power everything you say on this table will be heard. :)
The 'I'm right here and I disagree with your idea of killing me' became a running gag. As a player, I fall into this too. Those dscussion were kind of shorts anyway sowe never the 'I can hear you' as something really happening.
I've learned over the years of running campaigns that trying to institute some kind of "tabletop" rule doesn't work. The PCs will just find in-universe ways around it like through spells or radio tech, so I just let them have their conversations.
I found the best way to rein in the chatter is to let them have a couple minutes at an appropriate time, and if they want to go longer they take a -1 penalty to their rolls for each minute over. It works because it forces them to prioritize on what needs to be said instead of the stuff that just wastes our limited game time.
Although this page is stuff I'd let slide, since they're really just vocalizing what their characters are communicating through facial expressions and body language.