The person who started off this comment thread made a sloppy reference to "normal matter (i.e. quarks)". That statement should be read in good faith as meaning

The person who started off this comment thread made a sloppy reference to "normal matter (i.e. quarks)". That statement should be read in good faith as meaning the existing known elementary particles as "normal" matter. That implies that some particle which only interacts via gravity and some unknown force is not included in "normal" matter. To twist that by claiming such a particle would still be viewed as matter just like all the rest of the matter that goes into the stress-energy tensor is where the pedantry started in this thread. The original statement is pretty clear in its intent. The pedantic reading that followed that comment results in "normal" matter just being all matter by definition and hence "normal" is redundant since there can't be abnormal matter. That clearly isn't what the first comment intended since they actually meant something by "normal".