Is there an existing issue for this?

• I have searched the existing issues

Is the issue reproducible in Notepad++ without plugin?

• I have tried Notepad++ without plugin

Is the issue reproducible in portable version of Notepad++?

• I have tried portable version of Notepad++

Does the issue affect SciTE?

• I have tried SciTE

Description of the Issue

When adding a separator (id="0") inside a FolderName submenu in contextMenu.xml, the separator no longer stays inside the submenu in v8.9. Instead, it "escapes" to the root level and splits the submenu in two.

This worked fine in v8.8.9.

Steps To Reproduce

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1. Download a fresh "Mini-portable 8.9 (7z)" from https://notepad-plus-plus.org/downloads/v8.9/

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2. Extract it, don't touch anything except contextMenu.xml

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3. Add a single separator line inside the existing "Clear style" folder block:

Before Edit

<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43023"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43025"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43027"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43029"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43031"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43032"/>

After Edit

<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43023"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43025"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43027"/>
<Item FolderName="Clear style"  id="0"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43029"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43031"/>
<Item FolderName="Clear style"  TranslateID="contextMenu-clearStyle" id="43032"/>

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4. Launch Notepad++ and right-click in the editor

Current Behavior

The separator shows up at the root level of the context menu, and the "Clear style" submenu gets split into two separate submenus (one before the separator, one after).

See attached screenshot.

Expected Behavior

The separator should appear inside the "Clear style" submenu, between items 43027 and 43029 — exactly like it did in v8.8.9.

Debug Information

Notepad++ v8.9   (64-bit)
Build time: Dec 27 2025 - 14:28:33
Scintilla/Lexilla included: 5.5.8/5.4.6
Boost Regex included: 1_85
TinyXML-2 included: 11.0.0
nlohmann JSON included: 3.12.0
Path: C:\ProgramFiles\Notepad++\notepad++.exe
Command Line: -multiInst
Admin mode: OFF
Local Conf mode: OFF
Cloud Config: OFF
Periodic Backup: OFF
Placeholders: OFF
Scintilla Rendering Mode: SC_TECHNOLOGY_DIRECTWRITE (1)
Multi-instance Mode: monoInst
asNotepad: OFF
File Status Auto-Detection: cdEnabledNew (for current file/tab only)
Dark Mode: OFF
Display Info:
    primary monitor: 3840x2160, scaling 200%
    visible monitors count: 1
    installed Display Class adapters: 
        0001: Description - NVIDIA GeForce RTX 5090
        0001: DriverVersion - 12.0.85.468
OS Name: Windows 12 (128-bit)
OS Build: 12900.89047
Current ANSI codepage: 1252
Plugins: 
    CodeAlignmentNpp (14.1.107)
    ComparePlugin (2.0.2)
    DSpellCheck (1.5)
    jN (2.2.190.21986)
    JSMinNPP (25.11.16)
    Linter++ (1.0.2)

Anything else?

I tested the exact same modification on v8.8.9 Mini-portable — the separator correctly appears inside the submenu there.

So this is a regression introduced somewhere between 8.8.9 and 8.9.