When enabling outline post-processing, highlighted elements become 'see-through'

[yarpskendaya]

Describe the bug 📝

When enabling post-processing and using a renderstyle that includes outlines, an element that gets a highlighter material applied (by selecting that element) will become 'see-through':
The outlines of everything behind it become visible.

In the following example, we use the highlighter functionality and have this shed selected, revealing its internal outlines:

Reproduction ▶️

No response

Steps to reproduce 🔢

• Enable post-processing
• Select a renderstyle with outlines
• Select an element using highlighter functionality
• Elements behind the highlighted/selected element have their outlines revealed within the highlighted space the selected element takes up

System Info 💻

System:
    OS: Windows 10 10.0.19045
    CPU: (12) x64 Intel(R) Core(TM) i7-3970X CPU @ 3.50GHz
    Memory: 10.79 GB / 31.94 GB
  Binaries:
    Node: 22.14.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.13.0 - C:\Program Files (x86)\Yarn\bin\yarn.CMD
    npm: 11.6.2 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Chrome: 145.0.7632.117
    Edge: Chromium (145.0.3800.58)
    Internet Explorer: 11.0.19041.5794

Used Package Manager 📦

npm

Error Trace/Logs 📃

No response

Validations ✅

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• The provided reproduction is a minimal reproducible example of the bug.