README

Notepad3

A fast, lightweight, Scintilla-based text editor for Windows






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Notepad3 is a free, open-source text editor with syntax highlighting for Windows. Built on the Scintilla editing component and Lexilla lexer library, it has a small memory footprint while being powerful enough for professional programming and everyday text editing.

 Notepad3 is based on code from Florian Balmer's Notepad2 and XhmikosR's Notepad2-mod. MiniPath is based on Florian Balmer's metapath.



 Features

 Editing
- Code folding with toggle-all support
- Bookmarks for quick navigation within files
- Word auto-completion with configurable fill-up characters
- Mark all occurrences of a selected word with occurrence count display
- Find and Replace with PCRE2 regular expression engine
- Focused View — filter display to show only lines matching the current word/selection (Ctrl+Alt+V), with fold, bookmark, and highlight modes
- TinyExpr++ — inline math expression evaluation with 80+ functions (type expression=? to evaluate in-place, use ${expr} in line numbering).
- Undo/Redo that preserves selection state
- Visual Studio–style copy/paste of the current line (when nothing is selected)
- Virtual space rectangular selection (Alt+Drag)
- Accelerated word navigation with configurable delimiters
- Insert GUIDs directly into your document
- Clipboard monitoring mode (/b command-line switch) — automatically pastes copied text at the caret, with configurable separators, timestamps, and startup minimize delay; stop via Edit → Toggle Clipboard Monitoring without closing the editor.

 Syntax Highlighting
Over 55 languages supported, including:

 ANSI Art, ANSYS APDL, Apache Config, Assembly, AutoHotkey, AutoIt3, AviSynth, Awk, Batch, C/C++, C, CMake, CoffeeScript, CSS, CSV, D, Dart, Diff, F77/Fortran, Go, HTML/XML, Java, JavaScript, JSON, Julia, Kotlin, KiXtart, LaTeX, Lua, Makefiles, Markdown, MATLAB, Nim, NSIS, Pascal, Perl, PHP, PowerShell, Python, R/S-Plus, Registry, Resource Script, Ruby, Rust, Shell Script, SQL, SystemVerilog, Tcl, TOML, VBScript, VHDL, Verilog, Visual Basic, YAML, and more.

 File Handling
- AES-256 Rijndael encryption/decryption (in-app and command-line batch tool)
- Encoding detection powered by uchardet
- File change monitoring with configurable check intervals
- .LOG auto-timestamp — files whose first line is .LOG get a fresh date + time appended on open, matching classic Notepad behaviour
- Emacs file variables support (encoding, mode, tab-width, etc.)
- File history that preserves caret position and encoding
- Portable design — runs from USB drives with relative path storage

 Search
- grepWin — integrated search-in-files tool with regex support (Ctrl+Shift+F)
- Hyperlink hotspot highlighting — Ctrl+Click to open in browser, Alt+Click to load in editor

 User Interface
- High-DPI aware with high-definition toolbar icons
- Dark mode support with customizable colors
- Customizable st