open https://gitlab.synchro.net/main/sbbs/-/issues/905

Example:
```
■ Main ■ 0:00:07 [5] USENET [1] alt.2600: /*

Message Groups Sub-boards

[1] Main 8
[2] DOVE-Net 23
[3] FidoNet 81
[4] fsxNet 12
* [5] test 0
[6] USENET Newsgroups 16

■ Main ■ 0:00:19 [5] USENET [1] alt.2600: /5
■ Main ■ 0:00:22 [5] USENET [1] alt.2600: *

Sub-boards of test Posts


■ Main ■ 0:00:25 [5] USENET [1] alt.2600:
```
Empty File Libraries likely present a similar issue.

Reported by deon (ALTERANT) on DOVE-Net.
--- SBBSecho 3.24-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

https://gitlab.synchro.net/main/sbbs/-/issues/905#note_6998

Empty File Libraries do *not* have this same issue because have and use `user_can_access_lib()` in js_file_area.c when creating the file_area.lib_list[] which filters empty libraries already.
--- SBBSecho 3.24-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

close https://gitlab.synchro.net/main/sbbs/-/issues/905
--- SBBSecho 3.24-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)