Reopening https://forums.mtgo.com/index.php?t...rced-me-to-submit-an-extra-card-in-deck.2015/ but this time I took a screenshot 
as you can see, Sideboard and Main Deck views are out of sync: Main deck says it's a 60 card deck when it's 59 (missing one Chrome Mox) and Sideboard is 16 cards (the missing Chrome Mox is there)
Also please notice how the Submit button is enabled, this is because the 4th Chrome Mox is actually in deck for game purposes but no matter what I do, I can't move the Chrome Mox from Sideboard to Main Deck.
I can confirm both post sb game started with 60 cards and between games 2 and 3 deck was sideboarded as expected
pre sb game id: 876318118 (bug)
post sb game id: 876318564
third game id: 876318740
as you can see, Sideboard and Main Deck views are out of sync: Main deck says it's a 60 card deck when it's 59 (missing one Chrome Mox) and Sideboard is 16 cards (the missing Chrome Mox is there)
Also please notice how the Submit button is enabled, this is because the 4th Chrome Mox is actually in deck for game purposes but no matter what I do, I can't move the Chrome Mox from Sideboard to Main Deck.
I can confirm both post sb game started with 60 cards and between games 2 and 3 deck was sideboarded as expected
pre sb game id: 876318118 (bug)
post sb game id: 876318564
third game id: 876318740