Aye, I think I found something:
VGUI2: Creating a panel - developer.valvesoftware.com
As of now, my C++ knowledge is close to zero, since I have been experimenting with C# in the past years, only…
If there is any way to just add a page / tab to the existing panel, I’d be more than happy to know about it. 
If there is no other way than using C++, I think I have to drop this idea (again). 
Thanks in advance!
EDIT (09:13 PM): I’ve also tried to somehow “squeeze” the controls I wanted to add into the existing “Black Mesa” tab, but there’s just not enough space left for 4 Labels and 3 Sliders…
Original thread text:
[COLOR=’#808080’]Good afternoon,
while browsing through some of the mod files I came to think about adding a new options tab to the in-game (options) menu itself (similiar to how the DEV-Team added their “Black Mesa” tab).
I did figure out how to add and change certain sliders and labels to said “Black Mesa” tab and to make them actually do something, but I can’t seem to figure out how to “duplicate” said Black Mesa options tab - so I can edit this duplicated tab.
There is an article in VALVe’s developer wiki I found.
It describes how to add controls for different ConVars.
What I am trying to do, is add a new tab for different controls (checkboxes, sliders, etc.) entirely (as illustrated in the image below).
Note: The above image shows, what I’m trying to accomplish (not entirely, but it would be a start).
Is there a way to do this?
Any help would be much appreciated!
Note 2: This may be the wrong subforum (I think it is), so if it is, please move this thread. I’d like to say sorry in advance, if that is the case. 
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