How to highlight active instance of a program when hovering over combined taskbar button?

Description of problem:

When I have many windows/instances of a specific program open, they are combined on the taskbar (which I love), but when I hover over the taskbar icon, I can't see which window/instance is open and active.

In Windows 10, I had customized my color settings so that the active window/instance of the application was highlighted in a brighter shade of my accent color, and then had chosen an accent color to maximize that contrast difference. I can't seem to figure out how to do that in Windows 11. I've searched the forums here, but I don't think I've found the exact same issue.

I have Windows 11 Enterprise, Version 25H2.

Example screenshot showing what I want:

All names have been redacted from this screenshot for privacy. In this screenshot, I have manually added highlighting to show what this feature looked like in Windows 10. In reality, all windows/instances of Word in the list are the exact same color and I can't tell which one in the list is open without looking for the file name. 

Use case:

I'm a teacher and like to grade my class's work simultaneously, one question at a time. For example, I grade question 1 for all students, then I grade question 2 for all students, etc. This speeds my work while maximizing grading consistency. I often have 20+ instances of Microsoft Word open at the same time, and I need to be able to switch from one Word window to the next without skipping any. Not looking for and reading the file name allows me to work faster and grade my students' work much more quickly, as well as with greater anonymity/consistency.

Not a good option:

• Registry edits, because of IT department restrictions
• 3rd party Windows customization software, because of IT department restrictions
• Grading from the browser using Office 365 with each student's work in its own tab, because I use comments to give detailed feedback and Word 365 does not have as many comment features as the desktop version
• Rolling back to Windows 10 or switching to Linux, because the content that I teach requires Microsoft Windows 11.

Failed attempts to solve the problem:

I have attempted these fixes without success:

• In Settings --> Accessibility --> Contrast themes, choosing a contrast theme.
• In Settings --> Personalization --> Colors, setting Choose your Mode to Custom and
  • Changing settings for "Choose your default Windows mode"
  • Changing settings for "Choose your default app mode"
  • Toggling "Transparency effects"
  • Changing the accent color to Manual, then trying several accent colors
  • Toggling "Show accent color on Start and taskbar"
  • Toggling "Show accent color on title bars and window borders"
• In Settings --> Personalization --> Taskbar -->Taskbar behaviors, changing settings for:
  • Toggling "Show flashing on taskbar apps"
  • Toggling "Show badges on taskbar apps"
  • Changing the settings for "Combine taskbar buttons and hide labels"
  • Changing the settings for "Show smaller taskbar buttons"

Your help/suggestions are greatly appreciated!