the focus mode button suddenly disappeared

Hi everyone so I usually had 4 buttons 
two for switching sides and settings
and another two for focus mode during game

the last two suddenly disappeared and i tried many things but with no avail
what should I do?

this happens when you manually adjust the board size

close the site and enter it again

I tried it and adjust the zoom to every single one starting from 250% to 40% 
and I didnt even change it , it just suddenly disappeared 
I always play on 100%

Hey @Harionago I had this one too recently, what fixed it for me was dragging the board to full size on the bottom-right icon to resize it.

I have it, but it doesn't do anything cause I'm actually at the maximum size for this button but not the maximum for the focus mode
thank you so much

If your window/tab/screen is too small or your browser Zoom too high, the option won't be available.

UPDATE: I GOT IT FIXED 
@Wind I didn't drag it 
I just pressed on it, nothing happened 
But it worked when I refreshed the page after pressing it 
THANK YOU

Great to hear @Harionago and thank you for sharing the solution also!

for certain buttons can be seen in settings