Apps with 'Make Taskbar Transparent' feature

Open Shell is a fork of the Classic Shell project for Windows that getting back the classic start menu to modern versions of Microsoft Windows.

Web-based customizable desktop environment for Windows 10/11 with tiling window management, widget personalization, theme adjustments, and taskbar layouts.

TranslucentTB is a lightweight utility that makes the Windows taskbar translucent/transparent.

TaskbarX gives you control over the position of your taskbar icons.

Monitors network bandwidth with live graphs, usage logs, and alerts, providing breakdowns of uploads, downloads, statistics, and customizable data reports.

TaskbarDock offers a few extra features to customize your Windows 10 taskbar.

TaskbarTools - Grants the ability to set the Windows Taskbar to any opacity and colour desired.

Crystal XP lets you adjust the transparency of open windows, but don't expect anything awe-inspiring. Crystal XP's comprehensive interface is reminiscent of Windows and offers its configurations in English and Dutch.