diff --git a/extension/CHANGELOG.md b/extension/CHANGELOG.md
index b18f83c9..b4a5918b 100644
--- a/extension/CHANGELOG.md
+++ b/extension/CHANGELOG.md
@@ -13,8 +13,12 @@ First preview.
 - Toolchains download on first use, checked against built-in hashes.
 - Compiler and emulator crashes send an error report to 8bitworkshop.com,
   following VS Code's `telemetry.telemetryLevel` setting. See the README.
-- The Atari 2600 now stops at breakpoints and steps by instruction, not by
-  frame, and can step back.
+- Debugging with <kbd>F5</kbd>: breakpoints on lines, functions and
+  conditions; step, step over, step out, step back and reverse continue;
+  a timeline to scrub through the recording while paused.
+- Debug views: registers, the machine's internal state (the IDE's Debug
+  Tree), symbols, a call stack walked from return addresses, and
+  disassembly. Memory opens in VS Code's Hex Editor.
 - `.s`, `.asm`, `.inc` and `.a` files in a project get the highlighting
   for the platform's CPU. `.acme` files get 6502 highlighting.
 - An `8bws` command in the integrated terminal builds and runs programs
diff --git a/extension/notes/PLAN.md b/extension/notes/PLAN.md
index a53e5622..303051b1 100644
--- a/extension/notes/PLAN.md
+++ b/extension/notes/PLAN.md
@@ -258,7 +258,7 @@ is; a `.c` file anywhere else sees nothing from us.
 **Rule 2: claim a language ID only where nobody else does.**
 
 - *Extensions only 8bitworkshop uses* (`.dasm`, `.ca65`, `.acme`, `.xa`,
-  `.nesasm`, `.z`, `.xasm`, `.lwasm`, `.vasm`, `.wiz`, `.ecs`, `.bb`,
+  `.nesasm`, `.zmac`, `.xasm`, `.lwasm`, `.vasm`, `.wiz`, `.ecs`, `.bb`,
   `.cc2600`, `.cc7800`, ...): list them in
   `contributes.languages[].extensions`, generated from `toolmeta.ts`.
   Before each release, check the Marketplace for collisions.
@@ -1453,6 +1453,12 @@ vicdual, williams, zx. Since then (2026-09-26), vcs and arm32 work too. These do
 | `vector-*` | no frames | Vector video isn't forwarded; the webview needs line drawing (`VectorVideo.drawLine` ops). |
 | `kim1` | no frames | LED display, no raster video; needs its own view. |
 
+**TODO: hidden until they run** (2026-09-29). `vector-z80color`,
+`vector-ataricolor` (no frames) and `williams-z80` (`Worker is not
+defined`) are in `SKIP_PLATFORMS` in `scripts/presetindex.ts`, so New
+Project and Open Example don't offer them. Take each out of that list once
+the survey shows it producing frames.
+
 Also:
 - **Start timeout.** A platform whose `start()` never settles leaves the
   panel blank with no error (the CLI already reports "never finished
@@ -2379,7 +2385,7 @@ do them when a platform is the priority (VCS needs 3–4).
    share; `scripts/syntaxes.ts` writes `out/syntaxes/`. `test/syntaxes.test.ts`
    tokenizes with `vscode-textmate` and checks `package.json` against
    `makeContributions()`. Only extensions no one else uses are claimed
-   (`.dasm .ca65 .xa .nesasm .z .zmac .sgb .xasm .lwasm`); `.s .asm .inc .a`
+   (`.dasm .ca65 .xa .nesasm .zmac .sgb .xasm .lwasm`); `.s .asm .inc .a`
    wait for per-project language assignment (Rule 2).
    - Decided: no C grammar of our own. C goes to clangd/cpptools with our
      headers, defines and shims (`cheaders.ts`, §4 "C: feed clangd and
diff --git a/extension/package.json b/extension/package.json
index e4b4054b..28a974b5 100644
--- a/extension/package.json
+++ b/extension/package.json
@@ -386,7 +386,6 @@
           "Z80"
         ],
         "extensions": [
-          ".z",
           ".zmac",
           ".sgb"
         ],
diff --git a/extension/scripts/assetpack.ts b/extension/scripts/assetpack.ts
index c4b6bf22..7c303c68 100644
--- a/extension/scripts/assetpack.ts
+++ b/extension/scripts/assetpack.ts
@@ -6,12 +6,11 @@
 //
 // writes <outDir>/8bitworkshop-<pack>-<ideVersion>-<hash>.tar.br and
 // out/assets.json. Upload the packs to the asset server (ASSET_URLS in
-// extension.ts). --quality trades size for speed: 11 (the default, for
-// releases) takes minutes; 5 takes seconds.
+// extension.ts). --quality trades size for speed: 11 (the default)
+// takes minutes; 8 is nearly as small and much faster.
 //
-// `npm run package` packs a quick (quality 5) bundle so dev installs work;
-// the release scripts (`npm run package:release`, `npm run vsce-publish`,
-// `npm run ovsx-publish`) pack at full quality first. `vscode:prepublish`
+// `npm run package` packs at quality 8, which we ship; `npm run
+// package:release`, `vsce-publish` and `ovsx-publish` pack at 11. `vscode:prepublish`
 // only builds, so vsce never repacks the assets on its own.
 
 import * as fs from 'fs';
diff --git a/extension/scripts/presetindex.ts b/extension/scripts/presetindex.ts
index d74e68c1..8ed947a3 100644
--- a/extension/scripts/presetindex.ts
+++ b/extension/scripts/presetindex.ts
@@ -21,7 +21,10 @@ import type { PresetIndex, TemplateInfo } from '../src/presettypes';
 // families from the IDE's platform menu that the extension can't run
 const SKIP_FAMILIES = ['MAME/Other', 'Interpreters'];
 // platforms we never offer in the extension, even if the menu lists them
-const SKIP_PLATFORMS = ['x86', 'vectrex', 'exidy', 'arm32'];
+// TODO: vector-* need vector video in the webview, williams-z80 a headless
+// sound Worker (notes/PLAN.md, "platforms that don't run in the extension")
+const SKIP_PLATFORMS = ['x86', 'vectrex', 'exidy', 'arm32',
+  'vector-z80color', 'vector-ataricolor', 'williams-z80'];
 
 const rootDir = path.resolve(process.argv[2] || path.join(__dirname, '../..'));
 const outFile = path.resolve(process.argv[3] || path.join(__dirname, 'presets.json'));
diff --git a/extension/src/syntaxgen.ts b/extension/src/syntaxgen.ts
index baf02c80..9a21a272 100644
--- a/extension/src/syntaxgen.ts
+++ b/extension/src/syntaxgen.ts
@@ -49,7 +49,7 @@ export const ASM_LANGUAGES: AsmLanguage[] = [
   {
     id: '8bws-z80', cpu: 'z80',
     aliases: ['Z80 Assembly', 'Z80'],
-    extensions: ['.z', '.zmac', '.sgb'],
+    extensions: ['.zmac', '.sgb'],
     opcodes: uniq([...K.opcodesZ80, ...K.opcodesGBZ80]),
     registers: K.registersZ80,
     conditions: K.conditionsZ80,