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Description of the Issue

When working with large files with syntax highlighting enabled, if there are a large number of lines, the editor often becomes unresponsive during folding and unfolding operations.

To address this issue, I have optimized the Notepad++ code based on the latest master branch as of today.
A total of 7 files were modified:
ScintillaEditView.h
ScintillaEditView.cpp
Notepad_plus.cpp
NppCommands.cpp
FindReplaceDlg.cpp
documentMap.h
documentMap.cpp

@donho You can download the complete modified code here:
notepad-plus-plus-master[20250114].zip

Steps To Reproduce

1. Open a large file with syntax highlighting enabled.
2. Perform folding and unfolding operations.
3. After folding, switch between tabs.

Current Behavior

The editor becomes unresponsive for a long time.

Expected Behavior

Let’s reduce the editor’s response time.

Debug Information

Notepad++ v8.7.5   (64-bit)
Build time : Dec 21 2024 - 05:13:03
Path : C:\Program Files\Notepad++\notepad++.exe
Command Line : 
Admin mode : OFF
Local Conf mode : OFF
Cloud Config : OFF
Periodic Backup : ON
Placeholders : OFF
DirectWrite : ON
Multi-instance Mode : monoInst
File Status Auto-Detection : cdEnabledNew (for current file/tab only)
Dark Mode : OFF
OS Name : Windows 11 Pro (64-bit)
OS Version : 24H2
OS Build : 26100.2605
Current ANSI codepage : 1252
Plugins : 
    mimeTools (3.1)

Anything else?

No response