Gnus is from Emacs repo.

Within Gnus, 

  [Chicago Export filters for Org-mode]
  http://repo.or.cz/w/JabRefChicagoForOrgmode.git/blob_plain/HEAD:/net.sf.jabref.export.Chicago.ODF(English)-1.2.jar


How does the above URL below. Is it partly in bold and partly in default
font.  (See attached screenshot) Specifically, the URL is fontified only
till "1" (but doesn't include trailing ".2.jar" part).


,---- How "1" is fontified
| Character code properties: customize what to show
|   name: DIGIT ONE
|   general-category: Nd (Number, Decimal Digit)
|   decomposition: (49) ('1')
| 
| This is an active area of a link (widget)Top.
| 
| 
| There are 2 overlays here:
|  From 4589 to 4697
|   face                 gnus-button
|  From 4589 to 4697
|   button               link (widget)Top
|   evaporate            t
|   face                 widget-button
|   follow-link          mouse-face
|   help-echo            "Follow the link"
|   keymap               [Show]
|   mouse-face           (highlight)
|   pointer              hand
| 
| 
| There are text properties here:
|   gnus-callback        gnus-button-push
|   gnus-data            [Show]
|   gnus-string          [Show]
|   mouse-face           highlight
`----

,---- How "2" is fontified
| Character code properties: customize what to show
|   name: DIGIT TWO
|   general-category: Nd (Number, Decimal Digit)
|   decomposition: (50) ('2')
`----

In GNU Emacs 24.3.50.23 (i686-pc-linux-gnu, GTK+ Version 2.20.1)
 of 2013-07-25 on debian-6.05
Bzr revision: 113532 eliz@gnu.org-20130724173642-f1rke7jwa9330n3t
Windowing system distributor `The X.Org Foundation', version 11.0.10707000
Important settings:
  value of $LANG: en_IN
  locale-coding-system: iso-latin-1-unix
  default enable-multibyte-characters: t

Major mode: Article