Nothing changed when running the command other than showing the path as you mentioned:
DataPanel.url /default
DataPanel URL : file:////var/folders/vt/ysdcsvzj1nq0tn6n3wf1f_ym0000gn/T/Neutron/0f5cc672-14a6-4638-975e-bd9c493b031c/data_view_rel.html
The contents of that folder:
~ % ls -l /var/folders/vt/ysdcsvzj1nq0tn6n3wf1f_ym0000gn/T/Neutron/0f5cc672-14a6-4638-975e-bd9c493b031c
total 9488
-rw-r--r-- 1 gus staff 2252625 Dec 6 10:01 OfflineJS.zip
drwxr-xr-x 311 gus staff 9952 Dec 6 10:01 assets
-rw-r--r-- 1 gus staff 572 Dec 6 10:01 blocked_client_view_rel.html
-rw-r--r-- 1 gus staff 522 Dec 6 10:01 blocked_os_view_rel.html
-rw-r--r-- 1 gus staff 28185 Dec 6 10:01 create_branch_rel.html
-rw-r--r-- 1 gus staff 27394 Dec 6 10:01 create_milestone_rel.html
-rw-r--r-- 1 gus staff 209782 Dec 6 10:01 dashboard_rel.css
-rw-r--r-- 1 gus staff 1744430 Dec 6 10:01 dashboard_rel.js
-rw-r--r-- 1 gus staff 2729 Dec 6 10:01 data_view_rel.css
-rw-r--r-- 1 gus staff 330 Dec 6 10:01 data_view_rel.html
drwxr-xr-x 12 gus staff 384 Dec 6 10:01 font
-rw-r--r-- 1 gus staff 96380 Dec 6 10:01 jquery-1.11.0.min.js
-rw-r--r-- 1 gus staff 407099 Dec 6 10:01 manage_rel.html
-rw-r--r-- 1 gus staff 49443 Dec 6 10:01 merge_rel.html
-rw-r--r-- 1 gus staff 9584 Dec 6 10:01 simple_sharing_public_link_rel.html