It is not possible to use Display Suite fields with modules that depend on Field Formatter Settings module because Display Suite does not pass the field formatter settings in $context. See here and here.
Oh, just got a Notice: Undefined index: formatter_settings in [...] so we should check whether formatter_settings exists.
Notice: Undefined index: formatter_settings in [...]
That is just for building the summary? Right?
Committed and pushed, thanks.
Well re-evalutate later for D8, we need to rework that part anyway.
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