Sample showcase styling is broken for VFX learning templates ⏬

Steps to reproduce:

1. Open the attached project
2. Open HDRP_VFX_Learning_Templates Scene
3. Select the Sample_Showcase object in the Hierarchy
4. Observe the Inspector window

Actual results: Covered Aspects list items have broken styling. E.g - <margin=1em>Strip Output Context

Expected results:* Covered Aspects is styled as a bullet point list

Reproducible with versions: 6000.3.0a5

Not reproducible with versions: 6000.0.56f1, 6000.1.16f1, 6000.2.2f1, 6000.3.0a4

Tested on (OS): Windows 11, macOS 15.6

*Note from [~pauld] (formerly assigned to VFX area)
!image-2025-08-22-07-59-51-830.png|thumbnail!

The Text entry have the following content

{code:html}
<link="MultiStripGPUEvents.vfx"><color=#7AA8EEFF>Open VFX</color></link><br><link="VFXG Multi-Strips GPU-Events"><color=#FFE373FF>Show VFX</color></link><br><br>There are several ways to spawn particles, and when dealing with <b>strips</b>, this can have some implications for how you need to set up your VFX. This example illustrates how to circumvent the usual limitation that only permits the creation of one strip per parent's particle when dealing with <a href="https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@latest/index.html?subfolder=/manual/Block-TriggerEventRate.html&quot;>Trigger Events</a>. Each headphone jack is made of a particle mesh and spawns particles along its path.<br><br><b>Covered Aspects</b>:<br><margin=1em>• <a href="https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@latest/index.html?subfolder=/manual/Context-OutputShaderGraphStrip.html&quot;>Strip Output Context</a><br></margin><margin=1em>• <a href="https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@latest/index.html?subfolder=/manual/Operator-GetAttributeStripIndex.html&quot;>Strip Index</a></margin>
{code}

Thus, it can be reproduced with a simplest repro

{code:C#}
public class ReproRichText : EditorWindow
{
[MenuItem("CLICK HERE FOR REPRO/Repro Rich Text")]
public static void ShowExample()
{
ReproRichText wnd = GetWindow<ReproRichText>();
wnd.titleContent = new GUIContent("Simple Label");
}

public void CreateGUI()
{
var myLabel = new Label();

myLabel.text =
"<link=\"MultiStripGPUEvents.vfx\"><color=#7AA8EEFF>Open VFX</color></link><br><link=\"VFXG Multi-Strips GPU-Events\"><color=#FFE373FF>Show VFX</color></link><br><br>There are several ways to spawn particles, and when dealing with <b>strips</b>, this can have some implications for how you need to set up your VFX. This example illustrates how to circumvent the usual limitation that only permits the creation of one strip per parent's particle when dealing with <a href=\"https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@latest/index.html?subfolder=/manual/Block-TriggerEventRate.html\">Trigger Events</a>. Each headphone jack is made of a particle mesh and spawns particles along its path.<br><br><b>Covered Aspects</b>:<br><margin=1em>• <a href=\"https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@latest/index.html?subfolder=/manual/Context-OutputShaderGraphStrip.html\">Strip Output Context</a><br></margin><margin=1em>• <a href=\"https://docs.unity3d.com/Packages/com.unity.visualeffectgraph@latest/index.html?subfolder=/manual/Operator-GetAttributeStripIndex.html\">Strip Index</a></margin>";
myLabel.enableRichText = true;

rootVisualElement.Add(myLabel);
}
}
{code}

!image-2025-08-22-08-11-13-947.png|thumbnail!
!image-2025-08-22-08-18-35-016.png|thumbnail!