I get spoilers about the card that will come out while opening a pack.

What exactly is the problem here?  You described more or less how the Badges (Emblem XP) notification system works. 

It needs to be pointed out that when you get a card from the Market, the notification appears after you convert the player to a non-tradeable card, not at purchase from the market time.
Also, once you open a pack, the resource has already been spent. There is no way to reverse the outcome or get your resources back at that point, regardless of when the notification appears. So functionally, nothing changes, and that is expected behaviour.

The issue here is this: when you look at the image I attached, you can see that I haven’t opened the pack yet, but the Emblem XP update notification has already appeared. However, the Emblem XP update notification should only appear after the card intro is completed or after the card inside the pack is revealed. If it appears before I open the pack, I can already tell the amount of XP the card will give, or even know whether there will be no notification at all, which gives me information about the card before it is revealed. This is what we call a spoiler.

Still not an issue, the screenshot shows you already spend gems/fp so when you got a pack from the store, thats when the card was assigned, whether you open it straight away or a few mins later, its still gonna be the same card irrespective of what the notification you call a spoiler.  

I’m sorry, I thought the FC Mobile team was professional. In the Star Talent Scout, when the Card Program appears, the images shown on the right side of the specified card—for example, the Festival Fixtures card—do not have a visual effect behind the 110 OVR player card, whereas players with 114–115 OVR do have a visual effect behind them. Calling such fine mistakes “not an error, we did it that way on purpose” is very disappointing. If I had known it was like this, I wouldn’t have contributed by investing. Additionally, your tone is very inappropriate. Phrases like “you more or less explained the system as if you were criticizing us, so where is the problem?” come across as if you don’t understand at all. It’s very disappointing.

I am aware that after a purchase is made, the code already assigns the card before the pack is opened. I only reported it because giving a spoiler like this is unpleasant, and I expected a professional response such as “Thank you for your feedback, we will review it with our development team” or “we will evaluate it.” When this is something that could be resolved with a single line of code, and my intention was not to insult or offend you, I have no further questions. You may close the ticket

You realise, this is a public forum and I do not work for EA. I am just a player like you are.  Anyway, what you claim to be an issue, is not really one as it has no bearing on the outcome and does not stop you from playing or progressing. You also are ignoring the fact that some of the player base like me, may like this little "spoiler" as you call it, You don't and there will be others who simply couldn't care less. At the end of the day, it's a difference of an opinion on one's experience but my point remains, its not a bug, nor an issue with the game.

Have a good Xmas.