In looking up Opera GX settings, came across some vids that show Opera GX settings having an Advanced settings heading, with options contained within. My installed version has no such thing. Why is that? How do I find/unlock it?

Opera GX bookmark sidebar features empty space [forced padding] on
the left and right of bookmarks displayed. I'd like to see some added UI
settings to adjust that.

For reference, right side padding is approximately 2 cm of empty space on my 2k display, which is consuming a good chunk of horizontal screen real estate, which I'd prefer be used to display more of my bookmark's name/label.

Sidebar bookmarks feature icons, bookmark name/label, and the base website name it goes to.

a] Icons are great and require no translation.

b] The appended website name requires translation, and seems
to force significant amounts of truncating of the bookmark
name/label, ouch.

 Suggest removing the superfluous website part, or
 add a UI toggle to hide/show those.  And if a user elects 
 to hide that, also remove the truncating effect that it 
 applied to displaying bookmark names/labels.

Set minimum width for the bookmark bar to be approximately 2 cm wide.

[Currently the min width is set to a very silly & excessive 8.5 cm on my 2k display]

Bookmark Sidebar:

1] Min width for the bookmark bar ought to be approximately 2 cm wide. Atm min width is ludicrous at 8.5 cm

2] Bookmarks feature icons, bookmark name/label, and the base website name it goes to.

a] Icons are great and require no translation.
b] The appended website name requires translation, and seems 
     to force significant amounts of truncating of the bookmark 
     name/label [This is REALLY awful, and atm forces me to have 
     an extremely wide bookmark sidebar to be able to even read 
     my bookmark names/labels].  

     Suggest removing that entirely.
     Or add a UI toggle to hide/show those.  And remove the 
     truncating effect that it applied to displaying bookmark 
     names/labels.

3] Bookmark sidebar features empty space [forced padding] on
the left and right of info displayed. I'd like to see some UI
settings to adjust that.

 Myself, I'd prefer a bit less padding on the left, and much
 less padding on the right.  For reference, right side padding 
 is approximately 2 cm of empty space, which is consuming  
 a good chunk of horizontal screen real estate but provides zero 
 value

4] The bookmark sidebar response speed on dragging a bookmark
over to it, needs a UI setting.

Atm it is very fast, which when I mouse over a folder, that is 
not my target to place the link into, it rapidly displays the 
folder, and when the folder had many bookmarks, it can make 
dropping a link quite difficult.  Would favor more of a delay 
before it automatically displays a folder I mouse over.

In looking up Opera GX settings, came across some vids that show Opera GX settings having an Advanced settings heading, with options contained within. My installed version has no such thing. Why is that? How do I find/unlock it?

Installed Opera GX about a week back. Nice browser!

Curious though, any way to reduce the width of the bookmark sidebar? It's as narrow as Opera GX allows, which is not very narrow in my view. It's far wider than I usually set my bookmark sidebar, in other browsers. Why the limit? There is a lot of dead space in the panel, having it so wide, would be nice if I could reduce it about 50% less wide than the current min width allowed.

[Bonus, bookmark labels in the sidebar cut off kind of short. Any option incoming soon, to let us set it to show more of the label before it cuts off?]