If I can't see what games I already own on the store then I just leave the site. I am too old and probably own too many games to remember all of them. If the store doesn't help me to remind what I already own, a feature that you used to have, then I simply f*ck off.

Is this only my problem, a bug or is this how things now are here?

If you took the time to read the forms, you would know this is a bug being worked on. One of the users found a workaround for it. Also, the feature is working fine on Galaxy right now.

I'm not young but can remember the over 1600 games I have on GOG.

If you already own a game and try to buy it, the button says "Buy as a gift" instead of "Add to cart". You can't really accidentally buy the same game twice.

Use https://embed.gog.com/games for now. You may need to press CTRL+F5 to make the filters appear.

But yeah, it's been broken for over a week now.

Sorry, I'm not a galaxy user. But thanks for the information. Actually you can. At least with certain games you can. If you own gold or ultimate or platinum or whatever bundle then the other bundles or nonbundles of the same game shows as unowned. Even if you have the most complete bundle then the base game still doesn't show as owned even though you do. It's bit different problem I'm having right now but problem never the less. But thank you anyway. This is actually super helpful. Thank you.

No problem I actual understand your frustration. Did you find the thread with the workaround?

Edit: Never mind looks like SargonAelther saved the day.

It's not about whether GOG puts the "owned" label on the game in the store or not. If your account owns the game, the "Add to cart" option becomes "Buy as a gift". Being part of a collection doesn't change that.

For example I own the Mafia Trilogy, but attempting to purchase Mafia: Definitive Edition will still have "Buy as a gift" and not "Add to cart". Likewise I own the Yakuza Remastered Collection, and attempting to buy Yakuza 3 Remastered will show "Buy as a gift" and not "Add to cart".

Even when the store filters don't properly displayed which games you own, GOG still knows if the game is tied to your account or not.

In an ideal world, you'd be correct. It's supposed to be like this, but in reality it's not perfect.
Ennson is actually correct: GOG's database doesn't always "know" if you already own some content of games, and you can indeed purchase by mistake something you already own.

Darksiders Blades & Whip Franchise Pack
Doesn't flag Darksiders III Deluxe Edition nor DLC Darksiders III - Digital Extras DLC.

Frostpunk GOTY
Doesn't flag Season Pass DLC.

Stasis Bone Totem Supporters Pack DLC
Doesn't flag Soundtrack and Artbook DLCs.

This War of Mine Complete Edition
Doesn't flag Stories Season Pass

And you can by accident fully re-purchase these missed products without warning (add to cart) because the matching is insufficient. Blame GOG or the publishesr/devs if you wish, but this is only a mere fraction of examples where owning a "complete" version doesn't guarantee having all the individual stuff properly flagged.

This is a word of caution: don't take GOG's word that you don't already own things. Especially DLC stuff.

This means then that at least they have fixed it for some games. I checked one of my games and it still has "Add to cart" and "Buy now" instead of "Buy as a gift". And yes, it added it to my cart when I clicked it.

OK, so this doesn't work any longer. :(

Prior to the Halloween sale, GOG had restored the main store page filter options (probably not a coincidence). Simply visit: https://www.gog.com/games

If necessary, after visiting the aforementioned link, press [Ctrl]+[F5] (this bypasses out-of-date cache). There should no longer be an issue.

Note: On Mac, while using Chrome or Firefox, the equivalent would be: [Cmd]+[Shift]+[R] For Safari, you would need to hold down [Shift] and click the [Reload] button on the toolbar.

You don't need this any more, they fixed the regular store page.

Thanks, the Ctrl + F5 did the trick.