Joining a match in progress with animated card back reveals hidden information

When one joins (or rejoins) a match in progress, a lot of details on cards isn’t updated, I assume this much is known.

What I’m not sure is a known issue is that if either of the player has an animated effect on their card back, the animation will not play for cards until something changes about them.

Due to that, joining mid-game, one can tell which cards were added to hand since joining.

In the example provided, I see the leftmost 3 cards (from our perspective) appear to have no animation on them. Is it always the leftmost cards in such a scenario, or will the cards without animation change position in the hand as more cards are added?

The cards with animation were the cards that were added to hand (drawn or searched or returned). The non-animated ones were the ones that started there when I joined as a spectator.

Im asking if the cards that appear to have been added to hand are always in the same location in the hand, or do they get shuffled as cards are added.

The reason Im asking is because if the animated card backs are always in the same location in the hand, then its not actually revealing private knowledge or giving any real advantage, as the hand is actually shuffled every time a card is added, resulting in the animated card backs no longer aligning with the cards that were added.

If the animated card backs move around in the hand rather than being all on one side or something, then that indicates the animated card backs may be accurately following the location of the added cards, which of course would be an issue.

I believe they were in various locations but I can’t remember for sure anymore.