fix: luminance-aware chrome theming for light themes; serialized settings writes; buffered log flush

- Derive tab-bar/chrome palette by background luminance: light themes keep
  a near-background bar with black-tinted tab overlays instead of a muddy
  gray strip; dark themes unchanged
- Theme dockview tabs via the group-scoped --dv-*-tab-* vars its own rules
  consume (they outspecify our .dv-tab rules and leaked abyss navy onto
  light tabs); bump inactive-tab hover specificity to match
- Convert settings dialog + highlight editor hardcoded white text/border
  tints to color-mix over --chrome-fg so panes stay readable on light themes
- commands.ts: per-file log write buffer with a single drain loop per file
  (burst output coalesces into one appendFile per IO tick, chain no longer
  grows per logWrite); stop-tail rides the same buffer
- settingsStore: serialize all writers through mutateSettings() queue that
  re-reads latest state per mutation (tray close-action vs settings UI full
  saves no longer clobber each other)
- tests: burst ordering + stop-tail case for the log buffer

src/main/commands.ts

@@ -73,11 +73,15 @@ export class CommandsStore {
   /** Logs currently accumulating output, keyed by sessionId. */
   private readonly activeBySession = new Map<string, SessionLogMeta>()
   /**
-   * Pending append per log file. appendFile is async, so two rapid logWrite
-   * calls would otherwise race and land out of order. Chaining each new append
-   * onto the previous one keeps the file append-only in call order.
+   * Buffered plain text per log file, flushed by a single drain loop per file.
+   * Writes land in the buffer synchronously (so order is preserved) and the
+   * drain merges everything that accumulated during the previous appendFile
+   * round trip into one append call — burst output costs one syscall per IO
+   * tick instead of one Promise chain link per logWrite.
    */
-  private readonly pendingAppends = new Map<string, Promise<void>>()
+  private readonly logBuffers = new Map<string, string>()
+  /** In-flight drain loop per log file; absent when the file is settled. */
+  private readonly logDrains = new Map<string, Promise<void>>()
   /** Plain-text transformer per actively-logged session (see logSanitizer). */
   private readonly sanitizers = new Map<string, LogSanitizer>()
 
@@ -287,19 +291,35 @@ export class CommandsStore {
     // Raw PTY output is escape-sequence soup in a text file; log plain text.
     const clean = this.sanitizers.get(sessionId)?.push(data) ?? ''
     if (!clean) return
-    // Chain onto any in-flight append so rapid writes land in call order.
-    const prev = this.pendingAppends.get(meta.file) ?? Promise.resolve()
-    const next = prev.then(() => appendFile(meta.file, clean, 'utf8')).then(
-      () => undefined,
-      () => {
-        // file may have been removed after stop -> ignore
+    this.logBuffers.set(meta.file, (this.logBuffers.get(meta.file) ?? '') + clean)
+    this.drainLog(meta.file)
+  }
+
+  /**
+   * Flush a log file's buffer, keeping at most one drain (and therefore one
+   * in-flight appendFile) per file. New writes that arrive mid-flush re-enter
+   * the buffer and are picked up by the next loop iteration, merged.
+   */
+  private drainLog(file: string): Promise<void> {
+    const existing = this.logDrains.get(file)
+    if (existing) return existing
+    const run = (async (): Promise<void> => {
+      for (;;) {
+        const chunk = this.logBuffers.get(file)
+        if (chunk === undefined) break
+        this.logBuffers.delete(file)
+        try {
+          await appendFile(file, chunk, 'utf8')
+        } catch {
+          // file may have been removed after stop -> ignore
+        }
       }
-    )
-    this.pendingAppends.set(meta.file, next)
-    // Avoid unbounded growth of the chain map once the file settles.
-    next.finally(() => {
-      if (this.pendingAppends.get(meta.file) === next) this.pendingAppends.delete(meta.file)
+    })()
+    run.finally(() => {
+      if (this.logDrains.get(file) === run) this.logDrains.delete(file)
     })
+    this.logDrains.set(file, run)
+    return run
   }
 
   /** Stop logging a session, stamping endedAt into the registry + index. */
@@ -310,12 +330,8 @@ export class CommandsStore {
     this.sanitizers.delete(sessionId)
     if (tail) {
       // Best effort: the trailing partial line belongs in the file too.
-      const prev = this.pendingAppends.get(meta.file) ?? Promise.resolve()
-      const next = prev.then(() => appendFile(meta.file, tail, 'utf8')).then(
-        () => undefined,
-        () => undefined
-      )
-      this.pendingAppends.set(meta.file, next)
+      this.logBuffers.set(meta.file, (this.logBuffers.get(meta.file) ?? '') + tail)
+      this.drainLog(meta.file)
     }
     this.finishLog(meta)
   }

src/main/settingsStore.ts

@@ -159,25 +159,40 @@ export function loadSettings(): AppSettings {
   }
 }
 
-export function saveSettings(next: AppSettings): AppSettings {
-  const merged = deepMerge({
-    terminal: next.terminal,
-    customThemes: next.customThemes,
-    highlightRules: next.highlightRules,
-    system: next.system ?? DEFAULT_SYSTEM
-  }).settings
-  applySystemSettings(merged.system)
-  applyWindowChrome(merged)
-  const pretty = JSON.stringify(merged, null, 2)
+let settingsQueue: Promise<unknown> = Promise.resolve()
 
-  mkdirSync(app.getPath('userData'), { recursive: true })
-  const path = settingsPath()
-  const tmp = `${path}.tmp`
-  writeFileSync(tmp, pretty, 'utf8')
-  renameSync(tmp, path)
+/**
+ * Serialize a settings mutation against every other writer. Each queued step
+ * re-reads the file so the mutation applies on top of the latest state — a
+ * full-snapshot save can no longer silently revert a change written between
+ * its read and its write (e.g. tray close-action vs settings UI save).
+ */
+export function mutateSettings(mutate: (settings: AppSettings) => AppSettings): Promise<AppSettings> {
+  const run = settingsQueue.then((): AppSettings => {
+    const merged = deepMerge(mutate(loadSettings())).settings
+    applySystemSettings(merged.system)
+    applyWindowChrome(merged)
 
-  broadcast(Ipc.SETTINGS_CHANGED, merged)
-  return merged
+    mkdirSync(app.getPath('userData'), { recursive: true })
+    const path = settingsPath()
+    const tmp = `${path}.tmp`
+    writeFileSync(tmp, JSON.stringify(merged, null, 2), 'utf8')
+    renameSync(tmp, path)
+
+    broadcast(Ipc.SETTINGS_CHANGED, merged)
+    return merged
+  })
+  // Keep the queue alive when a mutation throws; the caller still sees it.
+  settingsQueue = run.then(
+    () => undefined,
+    () => undefined
+  )
+  return run
+}
+
+/** Replace the persisted settings with `next` (serialized). */
+export function saveSettings(next: AppSettings): Promise<AppSettings> {
+  return mutateSettings((current) => ({ ...current, ...next }))
 }
 
 export function registerSettingsIpc(): void {

src/main/tray.ts

@@ -1,6 +1,6 @@
 import { app, BrowserWindow, dialog, Menu, nativeImage, Tray } from 'electron'
 import type { SystemSettings } from '@shared/settings'
-import { loadSettings, saveSettings } from './settingsStore'
+import { loadSettings, mutateSettings } from './settingsStore'
 import trayIconPath from './assets/tray.png?asset'
 
 export type CloseAction = NonNullable<SystemSettings['closeAction']>
@@ -15,9 +15,12 @@ export function markQuitting(): void {
 }
 
 function persistCloseAction(action: CloseAction): void {
-  const next = loadSettings()
-  next.system.closeAction = action
-  saveSettings(next)
+  // Serialized read-modify-write on the latest state: must not stomp (or be
+  // stomped by) a concurrent full-snapshot save from the settings UI.
+  void mutateSettings((current) => {
+    current.system.closeAction = action
+    return current
+  })
 }
 
 function showMainWindow(showOrCreate: () => void): void {

src/renderer/src/global.css

@@ -5,6 +5,14 @@
   --chrome-border: #2d2d2d;
   --chrome-accent: #3b8eea;
   --chrome-hover: #2a2a2a;
+  --chrome-bg-deep: #101418;
+  /* Tab-bar overlays; overwritten per theme by applyChromeTheme(). */
+  --chrome-tab-bg: rgba(255, 255, 255, 0.04);
+  --chrome-tab-bg-hover: rgba(255, 255, 255, 0.07);
+  --chrome-tab-ring: rgba(255, 255, 255, 0.1);
+  --chrome-tab-ring-hover: rgba(255, 255, 255, 0.2);
+  --chrome-tab-fg: #98a2ab;
+  --chrome-tab-fg-hover: #d0d0d0;
 }
 
 html,

src/renderer/src/settings/highlight.css

@@ -1,5 +1,8 @@
 /* ============================================================
    Highlight settings tab + rule editor (settings/highlight.css)
+   Text/border tints derive from --chrome-fg via color-mix so the
+   panel follows the active terminal theme (white tints on dark
+   themes, black tints on light themes).
    ============================================================ */
 
 .hl-tab {
@@ -21,15 +24,15 @@
 }
 
 .hl-table .ant-table-thead > tr > th {
-  background: rgba(255, 255, 255, 0.04);
+  background: color-mix(in srgb, var(--chrome-fg, #cccccc) 4%, transparent);
   border-bottom: 1px solid var(--chrome-border);
-  color: rgba(255, 255, 255, 0.85);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 85%, transparent);
   font-size: 12px;
 }
 
 .hl-table .ant-table-tbody > tr > td {
   background: transparent;
-  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
+  border-bottom: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 6%, transparent);
 }
 
 .hl-table .ant-table-tbody > tr:hover > td {
@@ -48,7 +51,7 @@
 .hl-pattern-text {
   font-family: 'Cascadia Mono', Consolas, 'JetBrains Mono', monospace;
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.88);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 88%, transparent);
   overflow: hidden;
   text-overflow: ellipsis;
   white-space: nowrap;
@@ -71,17 +74,17 @@
 .hl-cell-priority {
   font-family: 'Cascadia Mono', Consolas, 'JetBrains Mono', monospace;
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.88);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 88%, transparent);
 }
 
 .hl-cell-note {
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.7);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 70%, transparent);
 }
 
 .hl-cell-empty {
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.3);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 30%, transparent);
 }
 
 .hl-preview-text {
@@ -114,7 +117,7 @@
 
 .hl-editor-label {
   flex: 0 0 56px;
-  color: rgba(255, 255, 255, 0.88);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 88%, transparent);
   padding-top: 5px;
 }
 
@@ -129,7 +132,7 @@
 .hl-editor-hint {
   align-self: center;
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.45);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 45%, transparent);
 }
 
 .hl-editor-error {
@@ -149,7 +152,7 @@
 
 .hl-editor-sub-label {
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.6);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 60%, transparent);
 }
 
 .hl-editor-inline {
@@ -170,7 +173,7 @@
   width: 40px;
   height: 26px;
   padding: 0;
-  border: 1px solid rgba(255, 255, 255, 0.2);
+  border: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 20%, transparent);
   border-radius: 4px;
   background: transparent;
   cursor: pointer;
@@ -197,7 +200,7 @@
 
 .hl-palette-tag {
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.5);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 50%, transparent);
   margin-right: 2px;
 }
 
@@ -205,7 +208,7 @@
   width: 16px;
   height: 16px;
   border-radius: 3px;
-  border: 1px solid rgba(255, 255, 255, 0.3);
+  border: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 30%, transparent);
   cursor: pointer;
   display: inline-block;
   transition: transform 0.12s ease, box-shadow 0.12s ease;
@@ -218,4 +221,4 @@
 .hl-swatch-selected {
   box-shadow: 0 0 0 2px var(--chrome-accent) inset;
   border-color: var(--chrome-accent);
-}
+}

src/renderer/src/settings/settings.css

@@ -1,5 +1,8 @@
 /* ============================================================
    Settings dialog + theme editor styles (settings/**, theme/**)
+   Text/border tints derive from --chrome-fg via color-mix so the
+   dialog follows the active terminal theme (white tints on dark
+   themes, black tints on light themes).
    ============================================================ */
 
 /* ---------- settings dialog scaffolding ---------- */
@@ -106,7 +109,7 @@
 }
 
 .settings-row:hover {
-  background: rgba(255, 255, 255, 0.03);
+  background: color-mix(in srgb, var(--chrome-fg, #cccccc) 3%, transparent);
 }
 
 .settings-row + .settings-row {
@@ -115,7 +118,7 @@
 
 .settings-row-label {
   flex: 0 0 46%;
-  color: rgba(255, 255, 255, 0.88);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 88%, transparent);
   font-size: 13px;
   line-height: 1.4;
 }
@@ -125,7 +128,7 @@
   margin-top: 2px;
   font-size: 12px;
   font-weight: 400;
-  color: rgba(255, 255, 255, 0.45);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 45%, transparent);
 }
 
 .settings-row-control {
@@ -156,7 +159,7 @@
 .settings-block-hint {
   font-weight: 400;
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.45);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 45%, transparent);
 }
 
 .settings-radio-group {
@@ -192,7 +195,7 @@
 .settings-preview-title {
   display: block;
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.5);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 50%, transparent);
   margin-bottom: 8px;
 }
 
@@ -247,14 +250,14 @@
   border-radius: 8px;
   overflow: hidden;
   cursor: pointer;
-  border: 2px solid rgba(255, 255, 255, 0.12);
-  background: rgba(255, 255, 255, 0.04);
+  border: 2px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 12%, transparent);
+  background: color-mix(in srgb, var(--chrome-fg, #cccccc) 4%, transparent);
   transition: border-color 0.15s ease, box-shadow 0.15s ease;
 }
 
 .theme-card:hover {
   border-color: var(--chrome-accent);
-  background: rgba(255, 255, 255, 0.07);
+  background: color-mix(in srgb, var(--chrome-fg, #cccccc) 7%, transparent);
 }
 
 .theme-card-selected {
@@ -280,7 +283,7 @@
 .theme-card-name {
   font-size: 13px;
   font-weight: 600;
-  color: rgba(255, 255, 255, 0.88);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 88%, transparent);
   overflow: hidden;
   text-overflow: ellipsis;
   white-space: nowrap;
@@ -293,7 +296,7 @@
   padding: 2px 5px;
   border-radius: 4px;
   background: rgba(59, 142, 234, 0.2);
-  color: #6fb3ff;
+  color: color-mix(in srgb, var(--chrome-accent, #3b8eea) 55%, var(--chrome-fg, #cccccc));
 }
 
 .theme-card-dots {
@@ -306,7 +309,7 @@
   width: 14px;
   height: 14px;
   border-radius: 3px;
-  border: 1px solid rgba(255, 255, 255, 0.25);
+  border: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 25%, transparent);
   display: inline-block;
 }
 
@@ -336,12 +339,12 @@
 .theme-card-new-icon {
   font-size: 26px;
   line-height: 1;
-  color: rgba(255, 255, 255, 0.55);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 55%, transparent);
 }
 
 .theme-card-new-text {
   font-size: 13px;
-  color: rgba(255, 255, 255, 0.6);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 60%, transparent);
 }
 
 /* ---------- theme editor ---------- */
@@ -359,7 +362,7 @@
 
 .theme-editor-label {
   flex: 0 0 56px;
-  color: rgba(255, 255, 255, 0.88);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 88%, transparent);
 }
 
 .theme-editor-colors {
@@ -379,7 +382,7 @@
 
 .theme-editor-color-label {
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.7);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 70%, transparent);
   flex: 1 1 auto;
   overflow: hidden;
   text-overflow: ellipsis;
@@ -391,7 +394,7 @@
   width: 40px;
   height: 26px;
   padding: 0;
-  border: 1px solid rgba(255, 255, 255, 0.2);
+  border: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 20%, transparent);
   border-radius: 4px;
   background: transparent;
   cursor: pointer;
@@ -408,7 +411,7 @@
 
 .theme-editor-divider {
   grid-column: 1 / -1;
-  border-top: 1px solid rgba(255, 255, 255, 0.1);
+  border-top: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 10%, transparent);
   margin: 2px 0;
 }
 
@@ -419,7 +422,7 @@
 .theme-editor-preview-label {
   display: block;
   font-size: 12px;
-  color: rgba(255, 255, 255, 0.5);
+  color: color-mix(in srgb, var(--chrome-fg, #cccccc) 50%, transparent);
   margin-bottom: 6px;
 }
 
@@ -495,7 +498,7 @@
 }
 
 .about-changelog {
-  border-top: 1px solid rgba(255, 255, 255, 0.08);
+  border-top: 1px solid color-mix(in srgb, var(--chrome-fg, #cccccc) 8%, transparent);
   padding-top: 12px;
 }
 

src/renderer/src/theme/chrome.ts

@@ -7,6 +7,17 @@ function parseHex(color: string): [number, number, number] | null {
   return [(n >> 16) & 255, (n >> 8) & 255, n & 255]
 }
 
+/** WCAG relative luminance (0=black, 1=white); null for non-hex input. */
+function luminance(color: string): number | null {
+  const c = parseHex(color)
+  if (!c) return null
+  const lin = c.map((v) => {
+    const s = v / 255
+    return s <= 0.03928 ? s / 12.92 : ((s + 0.055) / 1.055) ** 2.4
+  })
+  return 0.2126 * lin[0] + 0.7152 * lin[1] + 0.0722 * lin[2]
+}
+
 function toHex(v: number): string {
   return Math.max(0, Math.min(255, Math.round(v))).toString(16).padStart(2, '0')
 }
@@ -19,6 +30,10 @@ export function mix(a: string, b: string, t: number): string | null {
   return `#${toHex(ca[0] + (cb[0] - ca[0]) * t)}${toHex(ca[1] + (cb[1] - ca[1]) * t)}${toHex(ca[2] + (cb[2] - ca[2]) * t)}`
 }
 
+/** Whether the active terminal theme has a light background. Tab bars derived
+ *  from it flip their overlay direction (white-on-dark vs black-on-light). */
+let chromeIsLight = false
+
 /** Derive the app chrome palette (sidebar, tab bars, dividers) from the active
  *  terminal theme so the whole window follows theme switches instead of only
  *  the terminal canvas. Values land on :root CSS variables; anything the theme
@@ -30,13 +45,36 @@ export function applyChromeTheme(colors: ThemeColors): void {
   }
   set('--chrome-bg', colors.background)
   set('--chrome-fg', colors.foreground)
-  set('--chrome-bg-deep', mix(colors.background, '#000000', 0.35))
-  set('--chrome-hover', mix(colors.background, colors.foreground, 0.08))
-  set('--chrome-border', mix(colors.background, colors.foreground, 0.16))
+  chromeIsLight = (luminance(colors.background) ?? 0) > 0.5
+  if (chromeIsLight) {
+    // Light chrome: keep the bar close to the background (a big mix toward
+    // black turns pale themes into a muddy gray strip) and overlay tabs with
+    // translucent black instead of the translucent white used on dark themes.
+    set('--chrome-bg-deep', mix(colors.background, '#000000', 0.08))
+    set('--chrome-hover', mix(colors.background, '#000000', 0.06))
+    set('--chrome-border', mix(colors.background, '#000000', 0.2))
+    set('--chrome-tab-bg', 'rgba(0, 0, 0, 0.045)')
+    set('--chrome-tab-bg-hover', 'rgba(0, 0, 0, 0.09)')
+    set('--chrome-tab-ring', 'rgba(0, 0, 0, 0.18)')
+    set('--chrome-tab-ring-hover', 'rgba(0, 0, 0, 0.32)')
+    set('--chrome-tab-fg', mix(colors.background, '#000000', 0.68))
+    set('--chrome-tab-fg-hover', mix(colors.background, '#000000', 0.88))
+  } else {
+    set('--chrome-bg-deep', mix(colors.background, '#000000', 0.35))
+    set('--chrome-hover', mix(colors.background, colors.foreground, 0.08))
+    set('--chrome-border', mix(colors.background, colors.foreground, 0.16))
+    set('--chrome-tab-bg', 'rgba(255, 255, 255, 0.04)')
+    set('--chrome-tab-bg-hover', 'rgba(255, 255, 255, 0.07)')
+    set('--chrome-tab-ring', 'rgba(255, 255, 255, 0.1)')
+    set('--chrome-tab-ring-hover', 'rgba(255, 255, 255, 0.2)')
+    set('--chrome-tab-fg', '#98a2ab')
+    set('--chrome-tab-fg-hover', '#d0d0d0')
+  }
 }
 
-/** Tab accent: base color + a lightened foreground variant for text on dark
- *  tinted backgrounds. Consumed via var(--tab-accent*) in workspace.css. */
+/** Tab accent: base color + a foreground variant that stays readable on the
+ *  bar (lightened on dark chrome, darkened on light chrome). Consumed via
+ *  var(--tab-accent*) in workspace.css. */
 export function applyTabAccent(color: string): void {
   const style = document.documentElement.style
   // Settings hydrated from an older main process may lack the key; clear the
@@ -47,5 +85,6 @@ export function applyTabAccent(color: string): void {
     return
   }
   style.setProperty('--tab-accent', color)
-  style.setProperty('--tab-accent-fg', mix(color, '#ffffff', 0.18) ?? color)
+  const fg = chromeIsLight ? mix(color, '#000000', 0.35) : mix(color, '#ffffff', 0.18)
+  style.setProperty('--tab-accent-fg', fg ?? color)
 }

src/renderer/src/workspace/workspace.css

@@ -35,14 +35,14 @@
   border: none;
   border-radius: 5px;
   background: transparent;
-  color: #9a9a9a;
+  color: var(--chrome-tab-fg, #9a9a9a);
   font-size: 15px;
   cursor: pointer;
 }
 
 .workspace-rail-btn:hover {
   background: var(--chrome-hover);
-  color: #ffffff;
+  color: var(--chrome-fg, #ffffff);
 }
 
 .workspace-rail-divider {
@@ -54,7 +54,7 @@
 
 /* ---- M6.1 rail active state (mode entries) ---- */
 .workspace-rail-btn.is-active {
-  color: var(--dv-active-tab-foreground-color, #e8e8e8);
+  color: var(--tab-accent-fg, #e8e8e8);
   box-shadow: inset 2px 0 0 var(--tab-accent, #3fb950);
   background: color-mix(in srgb, var(--tab-accent, #3fb950) 10%, transparent);
 }
@@ -179,6 +179,18 @@
   /* Pane split dividers: soft slate band at rest, accent blue on hover/drag. */
   --dv-sash-color: rgba(148, 163, 184, 0.28);
   --dv-active-sash-color: rgba(59, 142, 234, 0.75);
+  /* Tab surfaces. Dockview paints tabs through group-scoped rules that
+     outspecify our .dv-tab rules, so theme the tabs via the vars those rules
+     consume — otherwise the abyss defaults (dark navy) leak onto light themes. */
+  --dv-activegroup-visiblepanel-tab-background-color: color-mix(
+    in srgb, var(--tab-accent, #3fb950) 10%, transparent);
+  --dv-activegroup-visiblepanel-tab-color: var(--tab-accent-fg, #3fd06a);
+  --dv-activegroup-hiddenpanel-tab-background-color: var(--chrome-tab-bg, rgba(255, 255, 255, 0.04));
+  --dv-activegroup-hiddenpanel-tab-color: var(--chrome-tab-fg, #98a2ab);
+  --dv-inactivegroup-visiblepanel-tab-background-color: var(--chrome-tab-bg, rgba(255, 255, 255, 0.04));
+  --dv-inactivegroup-visiblepanel-tab-color: var(--chrome-tab-fg, #98a2ab);
+  --dv-inactivegroup-hiddenpanel-tab-background-color: var(--chrome-tab-bg, rgba(255, 255, 255, 0.04));
+  --dv-inactivegroup-hiddenpanel-tab-color: var(--chrome-tab-fg, #98a2ab);
 }
 
 /* ---- tab polish: low rectangular tabs, quiet inactive, green active ---- */
@@ -191,16 +203,18 @@
   border-radius: 3px;
   padding: 0 8px;
   margin-right: 4px;
-  background: rgba(255, 255, 255, 0.04);
-  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.10);
-  color: #98a2ab;
+  background: var(--chrome-tab-bg, rgba(255, 255, 255, 0.04));
+  box-shadow: inset 0 0 0 1px var(--chrome-tab-ring, rgba(255, 255, 255, 0.1));
+  color: var(--chrome-tab-fg, #98a2ab);
   transition: background-color 0.12s ease, color 0.12s ease, box-shadow 0.12s ease;
 }
 
-.workspace-dockview .dv-tab.dv-inactive-tab:hover {
-  background: rgba(255, 255, 255, 0.07);
-  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.20);
-  color: #d0d0d0;
+/* Group-scoped chain matches dockview's own specificity so the hover tint
+   wins over its group-level background rules. */
+.workspace-dockview .dv-groupview .dv-tabs-container .dv-tab.dv-inactive-tab:hover {
+  background: var(--chrome-tab-bg-hover, rgba(255, 255, 255, 0.07));
+  box-shadow: inset 0 0 0 1px var(--chrome-tab-ring-hover, rgba(255, 255, 255, 0.2));
+  color: var(--chrome-tab-fg-hover, #d0d0d0);
 }
 
 /* XTerminal-style active tab: green outline + tinted bg + green title. */
@@ -229,7 +243,7 @@
   width: 15px;
   height: 15px;
   border-radius: 2px;
-  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.16);
+  box-shadow: inset 0 0 0 1px var(--chrome-tab-ring-hover, rgba(255, 255, 255, 0.16));
   opacity: 0.8;
   transition: background-color 0.12s ease, color 0.12s ease, box-shadow 0.12s ease;
 }
@@ -432,9 +446,9 @@ body.ssh-resizing .ssh-bottom-divider {
   padding: 0;
   border: none;
   border-radius: 6px;
-  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.16);
+  box-shadow: inset 0 0 0 1px var(--chrome-tab-ring, rgba(255, 255, 255, 0.16));
   background: transparent;
-  color: #98a2ab;
+  color: var(--chrome-tab-fg, #98a2ab);
   font-size: 10px;
   cursor: pointer;
   transition: background-color 0.12s ease, color 0.12s ease, box-shadow 0.12s ease;
@@ -464,18 +478,18 @@ body.ssh-resizing .ssh-bottom-divider {
   padding: 0;
   border: none;
   border-radius: 6px;
-  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.16);
+  box-shadow: inset 0 0 0 1px var(--chrome-tab-ring, rgba(255, 255, 255, 0.16));
   background: transparent;
-  color: #98a2ab;
+  color: var(--chrome-tab-fg, #98a2ab);
   font-size: 10px;
   cursor: pointer;
   transition: background-color 0.12s ease, color 0.12s ease, box-shadow 0.12s ease;
 }
 
 .workspace-tabbar-btn2:hover {
-  background: rgba(255, 255, 255, 0.07);
-  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.24);
-  color: #ffffff;
+  background: var(--chrome-tab-bg-hover, rgba(255, 255, 255, 0.07));
+  box-shadow: inset 0 0 0 1px var(--chrome-tab-ring-hover, rgba(255, 255, 255, 0.24));
+  color: var(--chrome-tab-fg-hover, #ffffff);
 }
 
 .workspace-tabbar-btn2.is-active {

tests/commands-store.mjs

@@ -198,5 +198,23 @@ ok(logs.find((x) => x.file === start.file).endedAt !== undefined, 'old log final
 store.openLogsDir()
 ok(openedPath === join(userData, 'logs'), 'openLogsDir resolves to the logs dir')
 
+// ---- 6. Burst ordering + stop tail (per-file buffer + single drain) -------------
+const sid2 = 'aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee'
+const startB = store.logStart(sid2)
+// Burst 1: 300 writes in one tick must coalesce into ordered appends.
+for (let i = 0; i < 300; i++) store.logWrite(sid2, `a${String(i).padStart(3, '0')}\n`)
+await wait(10)
+// Burst 2 after a gap: may land while burst 1's drain is still in flight.
+for (let i = 0; i < 100; i++) store.logWrite(sid2, `b${String(i).padStart(3, '0')}\n`)
+// Trailing partial line must ride the same buffer via logStop.
+store.logWrite(sid2, 'partial-tail')
+store.logStop(sid2)
+await wait(200)
+const expected =
+  Array.from({ length: 300 }, (_, i) => `a${String(i).padStart(3, '0')}\n`).join('') +
+  Array.from({ length: 100 }, (_, i) => `b${String(i).padStart(3, '0')}\n`).join('') +
+  'partial-tail'
+ok(readFileSync(startB.file, 'utf8') === expected, 'burst writes + stop tail land in order')
+
 console.log('\n[commands] ALL CHECKS PASSED')
 process.exit(0)