bottomline (-b) option is 0 indexed

[oredaze]

I don't know anyone who has their desktop numbers start at 0... This feature is useless if the number doesn't correctly correspond to the virtual desktop number.

[sagb]

Please show exact options you run attab with, and what do you see in bottom line.

[oredaze]

With default options it has -b 1 if I am not in single-desktop mode, which is true.
At the bottom right corner there is a number, it corresponds to the desktop number the application is on, you know how it works. However if my program is on desktop 1 it shows 0, if it is on desktop 2 it shows 1, etc...

[sagb]

The common standard for desktops (workspaces) is Freedesktop set of standards.
According to https://specifications.freedesktop.org/wm-spec/1.3/ar01s03.html

_NET_CURRENT_DESKTOP
The index of the current desktop. This is always an integer between 0 and _NET_NUMBER_OF_DESKTOPS - 1.

If your window manager generally conforms to this standard (alttab -v says "ewmh compatible"), then you can check how your WM assigns numbers to desktops: wmctrl -d

WM may also assign an arbitrary internal label to desktop number 0, making it, say, "1" for user. I doubt that incrementing standard integer value is reasonable. What if WM allows renaming the workspace to arbitrary text label? There is no standard way to obtain such labels.

[sagb]

Actually, there is a way to obtain this label. What wmctrl -d says for you?

[oredaze]

0  * DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  1
1  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  2
2  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  3
3  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  4
4  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  5
5  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  6
6  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  7
7  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  8
8  - DG: 1920x1080  VP: 0,0  WA: 0,0 1920x1080  9

This is openbox, and it correctly sets the index to 0. My point is that nobody considers starting with 0 when they work.
We set a hotkey and name to 1(maybe not always name...) for the first desktop (index 0). I guess I can just ignore that and never use it... but it's weird. Like when you login you start there...

[sagb]

Proper solution would be an option to display _NET_DESKTOP_NAMES/_WIN_WORKSPACE_NAMES.