diff --git a/CHANGELOG.md b/CHANGELOG.md
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+# Changelog
+
+## 4.0.0 (unreleased)
+
+### Visual Studio Code extension (preview)
+
+See [extension/CHANGELOG.md](extension/CHANGELOG.md).
+
+### Debugging and the `8bws` CLI
+
+- New `8bws` command-line tool (`npm run cli`) to build and run programs headlessly: `build`, `run`, `verify-replay`, `profile`, `detect`, `list-platforms`, `list-tools`; scripted emulator control; `--png`, `--json`, `--symbols`, `--memdump`, `--info`; platform and main file detected from a project directory.
+- Emulators now run on a timeline: step back, seek, reverse run, `rbreak`, and deterministic replay with a replay-verification test that found determinism bugs in several platforms.
+- Step Over for C and assembly sources, a Breakpoints pane, and more breakpoint conditions.
+- Call Stack view renamed Call Graph, with clocks and more detail per line.
+- Reset clears the call graph; breakpoints are re-armed after a build.
+- Click the hex offset in the gutter to run to that line.
+- Waveform viewer for Verilog, with help and shortcuts.
+- Faster line lookups in listings.
+
+### Editor and UI
+
+- Editor moved from CodeMirror 5 to CodeMirror 6 with Lezer grammars for 6502, Z80, 6809, Verilog, BASIC, batari BASIC, FastBasic, Inform 6 and Wiz; new Cobalt and MBO themes and better indent handling.
+- Source search across the project and toolchain headers (F1 for help), with arrow-key navigation, plus symbol search without source.
+- Shortcut bar and keyboard shortcut help, F8 pause/resume, Cmd+Shift+G go to offset.
+- Settings menu with developer options (highlight whitespace, highlight executed lines, line numbers off by default).
+- Hash routing for windows, and per-page titles.
+- Mobile layout: tab bar instead of split panes, and a flex toolbar.
+- Click `#include`/`#link` decorations to open the file; offer to import a GitHub repo given by `repo=` ("user/repo" or a tree URL).
+- Tool info dialog and generated toolchain docs; Help window with ID docs.
+- File | New only lists extensions that have skeleton files.
+- Removed the Markdown/Showdown platform, the old `script` platform, Google Analytics, Sentry (replaced with a new error-reporting endpoint) and the HTTPS redirect.
+
+### Asset editor
+
+- Undo/redo for edits, including binary files, and reliable undo for palette changes.
+- Clickable decorations with start/end line numbers, header and error display, and `#asseteditor/file/line` links.
+- Canvas up to 800x1000, interleaved pixel data, Apple II artifact colors, SMS/GG palette layouts, a large color picker, cut/paste, and `#embed` support.
+
+### Platforms
+
+- **Game Boy**: native emulator with GBC double speed, RTC and banking; C via a partial gbdk-2020 header set; presets ported from GBDK, plus Chase and Paku Paku; ghosting on the LCD.
+- **Atari 8-bit**: `.atr` disk images, 5th player, ANTIC and POKEY fixes, a8lib common library, scrolling and libdemo examples, oscar64 support.
+- **Atari 2600**: a Javatari-derived `vcs.jt4` machine that also runs headlessly; updated `vcs.h`/`macro.h`.
+- **Apple II**: paddle/joystick and SW0-2 support, dynamic origin, DOS 3.3 and AppleSingle samples.
+- **NES**: updated jsnes and a fix for a write bug.
+- **SMS/Game Gear/ColecoVision**: shared code, SMS Solarian port, more presets.
+- **Arcade**: Pac-Man hardware, Williams, Galaxian and Astrocade accuracy updates; early Exidy, MCR and Channel F work.
+- PC Engine Chase example; BASIC uppercase-only dialect fixes; 6502 KIL instructions halt the emulator.
+- C64: openroms-compatible cc65 `_cgetc`/`PLOT` overrides.
+- Verilog: fixed a non-convergence bug on settle and a shift-state bug on digit keys.
+- `.xa` assembler and the Dialog interactive-fiction compiler added.
+
+### Build tools
+
+- Many toolchains are now WASI builds: cc65 (pinned to 2021 6ac4aa4), DASM 2.20.17, acme, zmac, yasm and merlin32.
+- Updated batari BASIC; sdcc now parses `#symbol` directives and fixes lost link errors.
+- New build directives replace the legacy CFGFILE-style ones; build parameters no longer leak between builds.
+- `#pragma compile("...")` and oscar64 symbol/listing parsing.
+- Tool metadata centralized in `src/common/toolmeta.ts`; `npm run toolversions` checks tool versions.
+- Build is now only `esbuild` through `scripts/build.mjs`; code split into a headless `src/common/projectcore.ts` / `toolselect.ts`.
+- New `buildpresets` script that builds and runs every preset.
+
+## 3.12.1 (2025-11-06)
+
+- Verilog: FemtoRV32 RISC-V module and assembler fixes.
+- VCS: `atari2600-ecs.cfg` and better ECS section alignment; cc2600 added; cc7800 build updated.
+- Apple II: fixed the 0-9 keys.
+- Removed Sentry; updated esbuild and TypeScript 5.9.2; builds on Node 20.x.
+
+## 3.12.0 (2024-11-13)
+
+- New ARM32 platform with arm-tcc, libc, an ELF/DWARF parser and FPU instructions.
+- oscar64 compiler support (C64).
+- `#embed` directive for sdcc and cmoc.
+- Experimental Exidy platform; Astrocade arcade emulation work; Galaxian and Williams preset updates.
+- Verilog example categories; sdcc link errors no longer vanish when there are compile errors.
+- Debug info panel gets a close button; NES MMC3 RAM/SRAM areas swapped (issue #186); Apple II LC `$C08x` read fix.
+- Clarified the multi-license, and more C64 presets and a book link.
+
+## 3.11.0 (2023-11-06)
+
+- New PC Engine platform (32 KB carts, Wiz hello world).
+- VCS: preliminary cc65 support, TigerVision (3E/3F) mapper config, a vcslib demo.
+- Atari 7800: missing graphics modes, color kill, Kangaroo mode, PIA timer, 7800.h, and a Debug Tree for display lists.
+- Atari 8-bit: Debug Tree display list view.
+- C64: `.tap` export, Wiz support, updated music player and SID macros, LZ4 example; `incbin` for C files.
+- ca65: `.proc` symbols and listing parsing fixes.
+- Game controller D-pad switches and 2-button mapping; multiple controllers no longer interfere.
+- Removed the `script` platform and Google Analytics.
+
+## 3.10.1 (2023-05-11)
+
+- 6502 opcode stats corrected against TomHarte's ProcessorTests.
+- Atari 5200 menu item and presets; Atari 8-bit paddle inputs and music preset.
+- Fixed GitHub repository deletion; fixed C64 and vector-ataricolor presets.
+
+## 3.10.0 (2022-10-04)
+
+- New Atari 8-bit emulator, written in TypeScript and cycle-accurate. It replaces the MAME-based one, runs most cartridge games, and loads some well-behaved XEX files.
+- New CRT Probe colors: interrupt routines purple, DMA black, normal CPU activity grey with subtle tints for reads, writes and stack changes. Click the CRT Probe or Memory Probe to set a breakpoint.
+- New Sega Game Gear platform; the example code is shared with Master System.
+- Download Debug Symbols for NES, in Mesen format (contributed by NotExactlySiev).
+- Commodore 64: bug fixes, emulator improvements, many more examples (you may need to revert existing files).
+- Apple ][ improvements (contributions from micahcowan).
+- Single-stepping now switches between windows when appropriate.
+- New Help menu with tool- and platform-specific documentation, replacing the "?" button.
+- Better parsing of ca65 listing files, so line numbers are more accurate.
+- Fixed bugs with GitHub repositories and the browser back button.
+- Fixed keyboard issues on some computer platforms.
+- Fixed minor bugs in the 6502 and Z80 emulators.
+- Updated several compiler tools.
+
+## 3.9.1 (2022-09-13)
+
+Tagged the same day as 3.9.0; no separate notes.
+
+## 3.9.0 (tagged 2022-09-13; announced 2021-12-21)
+
+- The build now uses a JavaScript bundler (esbuild), improving modularity and startup time.
+- New Amstrad CPC platform (CPC6128, 128K) with the cpctelera library for C.
+- Stella (Stellerator) Atari 2600 emulator added to the MAME/Other menu: native TypeScript, CRT simulation, high accuracy, no IDE debugging.
+
+## 3.8.0 (2021-07-22)
+
+- New Verilog backend that translates modules to WebAssembly, based on Verilator 4: 20-50% faster, 64-bit support, better test compliance.
+- Verilog: Scope View swipe support and ergonomic improvements, inline assembler fixes, module state shown in the Debug Tree.
+- Updated the C64 and ZX emulators.
+- Fixed include/import issues in Silice and Wiz.
+- CC65 optimization flags can be overridden with `#define CC65_FLAGS <comma-separated args>`.
+
+## 3.7.2.1 (2021-05-21)
+
+- Upgraded Sentry.
+
+## 3.7.2 (2021-05-19)
+
+- VCS/DASM: better ca65 support (DASM is still preferred for VCS); better macro parsing (macros can be stepped through) and error messages.
+- Improved cycle analysis tool: counts up to 76*4 scanlines and inspects JSR subroutines.
+- The KIL ($02) instruction breaks into the debugger, usable for assertions.
+- Verilog: 32-bit RGB output supported when the upper 8 bits are set (`$FFbbggrr`); a lone module's inputs can be toggled by clicking the Scope view.
+- Experimental: Wiz, a "high-level assembly" language (examples for Atari 2600, NES, MSX).
+- Experimental: Silice, a semi-procedural HDL (slow to simulate).
+
+## 3.7.1 (2021-01-14)
+
+- Verilog 32-bit RGB output (`$FFbbggrr`), tested with Silice.
+- Embed mode: splits, UI tweaks, no line numbers, fixed `saveAs`.
+- Fixed GitHub import and branch-name bugs.
+- Serial test harness with `readFile`/`writeFile` and save/load state; `devel-6502` platform.
+
+## 3.7.0 (2020-10-08)
+
+- Vintage BASIC interpreter supporting multiple historical dialects via `OPTION DIALECT` (e.g. Dartmouth), with a teleprinter-style interface instead of a CRT.
+  - Errors are highlighted as you type; successful edits hot-load into a running program where possible.
+  - New "Restart at Line" button.
+  - Debug Tree and variable inspection by highlighting a name.
+- FastBasic, a BASIC interpreter for Atari 8-bit computers.
+
+## 3.6.0 (2020-07-23)
+
+New platforms:
+
+- Commodore 64 (chips library, MEGA65 open-source BIOS; C and 6502 assembly, no BASIC or disk drive).
+- ZX Spectrum 48K (SDCC for C, ZMAC for assembly, SEBASIC ROMs).
+- Z-Machine, with Inform 6 and its example games; includes a Debug Tree for object hierarchy and globals.
+- Atari 5200 (experimental; MAME-based, no debugging; Altirra BIOS).
+- PC DOS x86 (experimental; v86 with FreeDOS, yasm and SmallerC; no debugging).
+
+New tools and features:
+
+- Dithertron: converts images to retro formats (C64 multi/hires, NES, TMS9918A, Apple ][ Hires, Atari ANTIC D, Atari VCS, Bally Astrocade), with export to sample programs for some formats.
+- Probe Log: cycle- or instruction-level execution log.
+- Symbol Probe: running read/execute/write counts per symbol.
+- Call Stack: tree view with call counts and the raster lines where each subroutine starts and ends.
+- Debug Tree: inspector for raw emulator state.
+- All debug views now supported on VCS, C64 and ZX Spectrum.
+- Improved Memory Probe: more symbol lookups on mouse-over, display kept when advancing a frame.
+- Double-click a global symbol in the editor to show its value.
+- Cycle-level replay slider; opens the relevant listing while rewinding.
+- Run to PC by clicking the left gutter; fixed repeated use on the same line.
+- Fixed line numbers in CA65 assembly.
+- Requests browser storage permission on first new project or repository import (Safari) and reports whether changes will be preserved.
+- Memory Map shows overlapping segments side by side.
+- "?" toolbar icon links to platform/language help.
+- Downloaded ROMs get an appropriate file extension.
+
+## 3.5.2 (2020-06-28)
+
+- Multi-file import with `file0_name`; new upload dialog.
+- Started PC DOS support (v86, FreeDOS, FatFS, yasm, SmallerC).
+- Started Vectrex (xasm and C) and added the cmoc 6809 compiler.
+- C64: better PRG start address detection, F2/F4/F8/F10 keys, IRQ-based program start, ROM cart reset, clock correction, BIOS `gotoxy()` fix.
+- Fixed Apple II colors; Player 2 gamepad buttons; Verilog player 2 keys.
+
+## 3.5.1 (2020-04-09)
+
+- C64 added to the platform menu, with scrolling and sprite libraries.
+- Debug: variable values on inspect, textual probe view, click the gutter to run to cursor; probe output kept for the last frame.
+- Asset editor toolbar and aspect ratios.
+- Warns that Safari/iOS removes local data after 7 days.
+
+## 3.5.0 (2019-12-27)
+
+- Five new platforms, programmable in C or assembly: Bally Astrocade (with the open-source AstroLibre BIOS), ColecoVision, MSX (with open-source C-BIOS), Sega Master System, Atari 7800.
+- libCV C library shared by the TMS9918A-based platforms.
+- New Z80 simulator: much faster and no longer hiccups.
+- Memory Probe and CRT Probe debug views.
+
+## 3.4.2 (2019-09-08)
+
+- Quota errors caught on local storage, with a "persist" menu item.
+- Verilog: much faster `$readmem`, keycode/keystrobe, fixed the 6502 CPU.
+- GitHub: import after publish to get all files.
+- Uploads prompt for confirmation; audio buffers cleared when stopping.
+
+## 3.4.1 (2019-08-22)
+
+- Fixed audio autoplay in Chrome (VCS and SampleAudio).
+- GitHub: check the repo exists before importing.
+- Fixed POKEY/TIA sound, MSX presets and BIOS module, and Atari 7800 fixes.
+- Added nesasm3; NES `.asm` uses DASM instead of ca65.
+- Updated TypeScript to 3.5.3.
+
+## 3.4.0 (2019-08-10)
+
+- New Nintendo Entertainment System (NES) platform: C via cc65 with a fork of NESLib and Famitone for music/sound, plus 6502 assembly examples.
+- Project gallery of homebrew creations, openable in the IDE.
+- GitHub integration: publish projects to GitHub from a separate workspace. Limitations: all sources at the root; no conflict resolution (pulling replaces local files).
+- Asset Editor for palettes and bitmaps, writing changes back to source via comment tags.
+- Memory Map view of the platform's address space.
+- Profiler view with a scanline-by-scanline account of executing code.
+- Gamepad support, and keyboard controls shown while the emulator runs.
+- HTTPS is now the default for new users (File menu option to move existing users).
+- Verilog: `$readmemb` and `$readmemh`, Scope view icons, Ctrl-click the CRT to pause on a scanline, new "Verilog VGA" platform (slower, 25 MHz).
+- Minor: new dialog boxes, Z80 cycle counts in the assembler editor, more debug info, nicer break-expression dialog, new emulator focus ring.
+- Fixes: disappearing first editor line, debugging in listing view, segment names in Memory Viewer, DASM listing/error parser, assorted debugger issues.
+- New files no longer get a `local/` prefix (existing files keep it and can be renamed).
+
+## 3.3.0 (2018-12-22)
+
+- Verilog platform: write Verilog and see it simulated in real time on a simulated CRT (about 5 million ticks/sec in JavaScript), with a Scope view, many examples, and a built-in assembler for custom CPUs (e.g. FEMTO-8).
+- SDCC (Z80) now runs with `--oldralloc` for much faster compiles at slightly less optimal code. This breaks `bcd_add` and the vector game samples; use "Revert File" to restore the originals.
+- VCS: Ctrl-click the monitor to break when the raster beam reaches that position.
+- Binary files can be uploaded and included in 6502 assembly with `incbin`.
+
+## 3.2.1 (2018-11-25)
+
+- batari BASIC (Atari 2600) integrated, with presets from "Hello World" to complete games.
+- New sidebar and three resizable panes; shows source files, includes, listings and tools.
+- "Add Files to Project" menu items: new include files (`#include`) and linked C files (`//#link "..."`).
+- Markdown platform with live preview (Showdown).
+
+## 3.2.0 (2018-10-03)
+
+- Debugging keyboard shortcuts: Ctrl+Alt+P pause, R resume, `.` reset, S single step, V single frame, L run to cursor, O run until return, B step backwards.
+- Debugging of bankswitched VCS programs (standard 8K/16K/32K and Tigervision 3E/3F; ORG code at `$1000`). Force a mapper by appending its hex code to the filename, e.g. `MyGame[3E]`.
+- Apple ][ cassette loading via the c2t tool.
+- Bitmap Font Generator in the Tools menu.
+- Z80 disassembler.
+
+## 3.1.0 (2018-08-26)
+
+- VCS: header/include files viewable and editable (use double quotes, not angle brackets); fixed emulator blank-screen and wrong-size ROM bugs and a wonky PC when single-stepping; Advance Frame button; Disassembler view using DASM symbols; Stack Info in the Debug Info panel; `TIMER_START`/`TIMER_WAIT` made reliable for every scanline count (a WSYNC is now forced after `TIMER_WAIT`); new PAL example.
+- Instant Replay: records the last 120 seconds of game state to rewind and replay.
+- Share Playable Link: the whole ROM is embedded in the URL, embeddable via iframe.
+- Download ZIP archive of a project or of all changed files for a platform.
+- The page is no longer loaded twice on startup.
+- New Apple II+ (64K) platform with an alternate Monitor ROM (no Applesoft BASIC); C via cc65 and 6502 assembly.
+
+## 3.0.0 (2018-08-07)
+
+- New browser storage backend; local changes are migrated on first start, allowing many more saved projects.
+- HTTPS support (local files on HTTPS and HTTP sites are separate).
+- New WebAssembly worker build engine, much faster, with multiple include and link files.
+- Window list (folder icon) with listing files, Memory Browser and Disassembler views.
+- Error icons beside the editor expand to full messages on mouse-over.
+- VCS: no sound while the debugger is stopped; PIA and TIA state shown during debugging.
+- "Upload File" menu option.
+- Removed "Share File as GitHub Gist" due to GitHub changes.
+
+See the README for credits, third-party emulators, compilers and libraries, and the
+[GitHub contributors graph](https://github.com/sehugg/8bitworkshop/graphs/contributors) for the full list.
diff --git a/README.md b/README.md
index 7fdba947..c4992a69 100644
--- a/README.md
+++ b/README.md
@@ -155,6 +155,7 @@ Major contributors:
 * [Fred Sauer](https://github.com/fredsa) - CodeMirror 6 editor migration, Apple II enhancements, and general IDE work.
 * [Mike DX](https://github.com/MikeDX) - PC Engine / Game Boy / Williams 6809 enhancements, library code, and examples.
 * [Micah Cowan](https://github.com/micahcowan) - Apple II enhancements.
+- NotExactlySiev: NES debug symbols in Mesen format (3.10.0).
 
 The emulators, compilers, assemblers, and libraries that this project
 builds on are credited in [Dependencies](#dependencies) and retain their