Grouped avatar overlap and mask offset are not as designed

[jouni]

The mask offset (called “margin” in the mockup) and overlap of grouped avatars is too wide.

Compare to the design for correct spacings (#8 (comment)):

Current implementation (incorrect):

Design:

For the overlap, the abbreviations should be roughly equally visible regardless of the size variant. Currently, for example, the “FB” is being clipped too much in the smaller variants.