More tests.

test/default.md

+---
+markdown-underline:
+  '*': b
+---
 
 # Let's test the features!
 
@@ -6,15 +10,29 @@
 2. `_`: _underscore_
 3. `__`: __underscores__
 4. `~~`: ~~double tilde~~
-5. `~`: tilde
+
+
+_**__salient__**_
 
 ____
 
 #### Definition list
 
 <!-- definition lists -->
+
 celerity $c$
-: speed of light in a vacuum
+: Speed of light in a vacuum.
+
+circle constant $\tau$
+: Circumference of the unit circle.
+  
+  With multiline things and goodies like some *bold text*.
+  
+  Gumbo beet greens corn soko endive gumbo gourd.
+  Parsley shallot courgette tatsoi pea sprouts fava bean collard greens
+  dandelion okra wakame tomato. Dandelion cucumber earthnut pea peanut soko zucchini. 
+  
+  
 
 <!-- Trailing # are ignored and are sometimes good for readability -->
 ### Flowchart ########################################################