[Sm-126esr] GUI: Scrollbar related flags non-functional

[Vangelis66]

Describe the bug

In all releases thus far of Supermium 126, I find that all three scrollbar-related internal flags (inside chrome://flags/) do NOT have the desired effect when set to Enabled 😞 .

To Reproduce
Steps to reproduce the behaviour:

(Sm-v126-r4_32 was used)

1. Go to chrome://flags/
2. In the Search flags bar, input "scrollbar"; you'll get below three results:

4. Set, e.g., the first two of them to Enabled, then, as prompted, relaunch Sm-v126
5. Load e.g.
   https://github.com/win32ss/supermium/issues?q=is%3Aissue+is%3Aopen+sort%3Aupdated-desc
   and scroll down slightly; notice the appearance of the srollbar hasn't changed:

Expected behavior
A clear and concise description of what you expected to happen.

In Sm-v124/122/121, the Enabled flags produce the advertised effect, as shown below:

Screenshots
If applicable, add screenshots to help explain your problem.

See the ones above...

Desktop (please complete the following information):

• OS: Windows Vista SP2 x86, fully updated to EoS
• Bitness of browser: 32-bit, since my OS is x86 😉

Additional context
Add any other context about the problem here.

This isn't the end of the world, obviously 😄 , but my OCD gets worse with things like that (and there are many "such things" in v126, but I'll speak some other time about (some of) the rest 😉 ...

Thanks again for this browser 👍 !

[win32ss]

There is an issue with non-propagation of some features to renderer processes where they are ultimately implemented. The dark modes were previously affected, and so is this one.

[Vangelis66]

Hi 😄 ; the mentioned scrollbar flags work as designed in my "dirty" Sm-v124 profile.
In my dirty "Sm-v126" profile they simply don't; I tried --no-sandbox in that profile, without any change; I was also sad to find that running the dirty "Sm-v126" profile with --single-process made the browser immediately crash 😢 ; I can't be bothered to discover why (an extension, a cmdline flag, an internal flag?), because I'd never run the browser in single process here...

FWIW, I created a (temporary) fresh v126 profile and on that one the scrollbar flags WORK only when --single-process is issued; I always also use #force-dark-mode in my Sm profiles, this flag doesn't seem to affect the scrollbar flags (they do work when --single-process+--force-dark-mode are issued together).

As a workaround to this bug on my dirty Sm-v126 profile, and only for web content (because "those flags" also work in chrome:// pages in v124 and earlier), I'm using the Stylus userstyle ultimate-scrollbar 😉 ...

Regards.