They are still displayed several times.
Before #69a7499a, one LogControl in LN0 was displayed 6 times by EcoreUtil.getAllContents() because LN0 in LDevice was itself displayed twice and LogControl was displayed 3 times by LN0.
After #69a7499a, LogControl was displayed twice by LN0 (therefore 4 times in total).
FeatureMap are used to store LN0 (along with LN) in LDevice, and also to LogControl (along with ReportControl) in LN0.
Investigation should be done to understand if it is a misused of FeatureMap or an issue with EMF. In the meantime, use of FeatureMap should be removed.