1. Download imglib project:
git clone https://github.com/imglib/imglib.git

2. Switch to master branch (if needed)
git checkout master

3. The latest commit when I was testing was ad84253
git checkout ad84253

4. Compile the 'algorithms' module with ./imglib/algorithms/pom.xml

5. Go to ./imglib/algorithms/core/target folder

6. Launch sigtest
java -jar sigtestdev.jar Setup -classpath classes:$JAVA_HOME/jre/lib/rt.jar -static -package net.imglib2.algorithm -filename test.sig 2>&1 | grep Neighborhood

The output of the last command is

Warning: The return type net.imglib2.IterableInterval<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.IterableInterval<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.RandomAccessible<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.RandomAccessible<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.IterableInterval<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.IterableInterval<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.RandomAccessible<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved
Warning: The return type net.imglib2.RandomAccessible<net.imglib2.algorithm.region.localneighborhood.Neighborhood<{%%0}>> can't be resolved

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Additionally there are some fatal errors with sigtest -debug option:
java.lang.ClassNotFoundException

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I failed to write the minimal failing code.
Sigtest works Ok with both multiple inheritance and generics.