@ImprovingSkill,
You are right. I will explain something that I noticed after the analysis of the game.
I (white) was forced to surrender because my white bishop disappeared after the move #20 (
http://en.lichess.org/FBfSlQGn#20). Now, If you click on the link above, you'll see that the bishop is visible in the whole game. Bishop disappears only during the game.
I repeated this mistake. I played a game with yourself. I made screenshots.
Move #18:
http://linkme.ufanet.ru/images/5ad010f8d2659001a59cb95937223a40.pngMove #19:
http://linkme.ufanet.ru/images/8a05a1a089f14497e436ccccccccd458.pngMove #20 (bishop disappear):
http://linkme.ufanet.ru/images/8d94c534e4fdd899b35acdb82b48eee5.pngLast move:
http://linkme.ufanet.ru/images/ecb29aabed50dc225e520a5ac21af006.pngIn the last move I had no bishop, I thought it exploded at #20 move. I thought that the last move was supposed to be the mat and it's a bug.
In this last move I can not move anything, even invisible bishop. I still think it's a bug.
My browser Iceweasel 31.3.0.