Platform: PC.

1) Open store, go to Decks tab
2) There's an offer for "Foundation Deck: Brawl Heroes in a Half Shell". Click on the gem price to see details.
3) The "Confirm Purchase" page is displayed. There is a "View Deck" button on the top right hand corner. Click on Cancel.
4) Go to the Featured tab and click on the price of any offer. The "Confirm Purchase" page is displayed. There is a "View Deck" button on the top right hand corner which should not be there.
5) Click on the "View Deck" button. The "Foundation Deck: Brawl Heroes in a Half Shell" deck is displayed (unrelated to the current page!).
6) Click on the back button. It brings back to the Foundation Deck in the Decks tab.

Note: I have the same issue when going from the Decks tab to the Featured tab or the Bundles tab (step 4).