expand/close icon is white on white background

[ivan-ushakov]

Minor UI issue but could confuse user:

with red color:

[sosnovsky]

@tomholub I can work on this issue along with #936, as it's the same cell

[tomholub]

Ivan - well noticed. Roma - assigned. Thank you both!

[tomholub]

Btw this issue is not minor - it could be very confusing