Hello,

guess the commit c27c101f (08/16/2015 04:14 PM) with the title "org.el: Fix `org-comment-string' fontification" has chosen a bit too harsh 'fixation' method:

Since then, the 'org-special-keyword' face for 'COMMENT' is not applied to heading of lower levels any more but only to the top one.

The minimal example below also demonstrates another possibly unintended fontification.
Bold and italic faces (or the other options of http://orgmode.org/org.html#Emphasis-and-monospace) are extended across lists which they probably should not.

The two issues, however, seem not directly related and I do not know when the second one was introduced.

,---------------------------
| * COMMENT Level 1         
| ** COMMENT Level 2        
| *** TODO COMMENT Level 3  
| 1) load all *.el files    
| 2) tangle all org-* files 
| ***** TODO COMMENT Level 4
| 1) load all /*.el files   
| 2) tangle all org-*/ files
`---------------------------

Best,
mc

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