/usr/share/ne/syntax/tabs.jsf is in ne 3.0.1-2build1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 | # JOE syntax highlight file for text with visible tabs
=Idle
=Tab bg_cyan
:idle Idle
* idle
"\t" tab noeat
:tab Tab
* idle noeat
"\t" tab
|