From e0229917f8c69c541c37d8b7a542191454fd9b97 Mon Sep 17 00:00:00 2001
From: Leonid <127580858+bashrusakh@users.noreply.github.com>
Date: Sat, 11 Jul 2026 22:45:27 +1100
Subject: [PATCH] feat(settings): editor font size for chat input and code
 editor (#1325) (#2065)

* feat(settings): add editor font size setting for chat input and code editor

Adds an 'Editor font size' control in Settings > Appearance that sets an
absolute px font size for the chat input textarea and the in-app
CodeMirror editor. Mirrors the existing terminalFontSize lifecycle.

- New store field editorFontSize (default 13, clamp 9-32, step 1) in
  useUIStore with narrow selectors at each consumer.
- Persistence wired through appearanceAutoSave, desktop + runtime API
  types, and persistence.ts read/normalize.
- Settings UI row (NumberInput) with reset to 13, VisibleSetting union
  entry, OpenChamberPage registration, and search index entry
  appearance.editor-font-size.
- Applied as a post-zoom absolute override on the chat input textarea
  and on the CodeMirror theme's content rule, leaving gutter/line-number
  chrome at its existing hardcoded sizes (matches terminal scope).
- All 10 locales translated (en, es, fr, ja, ko, pl, pt-BR, uk, zh-CN,
  zh-TW); no English placeholders in non-English dictionaries.

Refs #1325

* fix(codemirror): use unitless lineHeight so it scales with editor font size

The & rule in the CodeMirror theme set lineHeight to 1.5rem (~24px),
which does not scale when editorFontSize is increased (e.g., 28-32px).
This causes overlapping lines at larger font sizes.

Change to unitless 1.5, which scales proportionally with whatever fontSize
resolves to (dynamic prop or --text-code fallback). Matches browser best
practice for proportional leading.

Review comment: https://github.com/openchamber/openchamber/pull/2065

---------

Co-authored-by: bashrusakh <bashrusakh@users.noreply.github.com>
Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>
---
 packages/ui/src/components/chat/ChatInput.tsx |  2 ++
 .../sections/openchamber/OpenChamberPage.tsx  |  1 +
 .../openchamber/OpenChamberVisualSettings.tsx | 35 +++++++++++++++++--
 .../components/sections/skills/SkillsPage.tsx | 11 +++---
 .../ui/src/components/views/FilesView.tsx     | 10 +++---
 packages/ui/src/components/views/PlanView.tsx |  6 ++--
 packages/ui/src/lib/api/types.ts              |  1 +
 packages/ui/src/lib/appearanceAutoSave.ts     |  6 ++++
 .../ui/src/lib/codemirror/flexokiTheme.ts     |  8 +++--
 packages/ui/src/lib/desktop.ts                |  1 +
 .../ui/src/lib/i18n/messages/en.settings.ts   |  2 ++
 .../ui/src/lib/i18n/messages/es.settings.ts   |  2 ++
 .../ui/src/lib/i18n/messages/fr.settings.ts   |  2 ++
 .../ui/src/lib/i18n/messages/ja.settings.ts   |  2 ++
 .../ui/src/lib/i18n/messages/ko.settings.ts   |  2 ++
 .../ui/src/lib/i18n/messages/pl.settings.ts   |  2 ++
 .../src/lib/i18n/messages/pt-BR.settings.ts   |  2 ++
 .../ui/src/lib/i18n/messages/uk.settings.ts   |  2 ++
 .../src/lib/i18n/messages/zh-CN.settings.ts   |  2 ++
 .../src/lib/i18n/messages/zh-TW.settings.ts   |  2 ++
 packages/ui/src/lib/persistence.ts            |  6 ++++
 packages/ui/src/lib/settings/search.ts        |  6 ++++
 packages/ui/src/stores/useUIStore.ts          | 10 ++++++
 23 files changed, 108 insertions(+), 15 deletions(-)

diff --git a/packages/ui/src/components/chat/ChatInput.tsx b/packages/ui/src/components/chat/ChatInput.tsx
index bae96284..c91780aa 100644
--- a/packages/ui/src/components/chat/ChatInput.tsx
+++ b/packages/ui/src/components/chat/ChatInput.tsx
@@ -1121,6 +1121,7 @@ const ChatInputComponent: React.FC<ChatInputProps> = ({ onOpenSettings, scrollTo
     const inputBarOffset = useUIStore((state) => state.inputBarOffset);
     const persistChatDraft = useUIStore((state) => state.persistChatDraft);
     const inputSpellcheckEnabled = useUIStore((state) => state.inputSpellcheckEnabled);
+    const editorFontSize = useUIStore((state) => state.editorFontSize);
     const isExpandedInput = useUIStore((state) => state.isExpandedInput);
     const setExpandedInput = useUIStore((state) => state.setExpandedInput);
     const setTimelineDialogOpen = useUIStore((state) => state.setTimelineDialogOpen);
@@ -5256,6 +5257,7 @@ const ChatInputComponent: React.FC<ChatInputProps> = ({ onOpenSettings, scrollTo
                                     maxHeight: !isComposerExpanded && textareaSize ? `${textareaSize.maxHeight}px` : undefined,
                                     borderTopLeftRadius: chatInputRadius,
                                     borderTopRightRadius: chatInputRadius,
+                                    fontSize: `${editorFontSize}px`,
                                 }}
                                 rows={1}
                             />
diff --git a/packages/ui/src/components/sections/openchamber/OpenChamberPage.tsx b/packages/ui/src/components/sections/openchamber/OpenChamberPage.tsx
index 37404f5c..8ae64f84 100644
--- a/packages/ui/src/components/sections/openchamber/OpenChamberPage.tsx
+++ b/packages/ui/src/components/sections/openchamber/OpenChamberPage.tsx
@@ -133,6 +133,7 @@ const VisualSectionContent: React.FC = () => {
         ...(!isVSCode ? ['weekStart' as const] : []),
         'fontSize',
         'terminalFontSize',
+        'editorFontSize',
         'fileEditorKeymap',
         'spacing',
         'inputBarOffset',
diff --git a/packages/ui/src/components/sections/openchamber/OpenChamberVisualSettings.tsx b/packages/ui/src/components/sections/openchamber/OpenChamberVisualSettings.tsx
index 2b39c81c..025cab13 100644
--- a/packages/ui/src/components/sections/openchamber/OpenChamberVisualSettings.tsx
+++ b/packages/ui/src/components/sections/openchamber/OpenChamberVisualSettings.tsx
@@ -245,7 +245,7 @@ const normalizeUserMessageRenderingMode = (mode: unknown): 'markdown' | 'plain'
     return mode === 'markdown' ? 'markdown' : 'plain';
 };
 
-type VisibleSetting = 'sessionAssist' | 'theme' | 'pwaInstallName' | 'pwaOrientation' | 'mobileKeyboardMode' | 'timeFormat' | 'weekStart' | 'fontSize' | 'terminalFontSize' | 'spacing' | 'inputBarOffset' | 'mermaidRendering' | 'userMessageRendering' | 'chatRenderMode' | 'messageTransport' | 'activityRenderMode' | 'collapsibleUserMessages' | 'stickyUserHeader' | 'wideChatLayout' | 'codeBlockLineWrap' | 'splitAssistantMessageActions' | 'diffLayout' | 'mobileStatusBar' | 'dotfiles' | 'fileViewerPreview' | 'reasoning' | 'showToolFileIcons' | 'showTurnChangedFiles' | 'expandedTools' | 'followUpBehavior' | 'terminalQuickKeys' | 'fileEditorKeymap' | 'persistDraft' | 'inputSpellcheck' | 'reportUsage' | 'expandedEditorToolbar';
+type VisibleSetting = 'sessionAssist' | 'theme' | 'pwaInstallName' | 'pwaOrientation' | 'mobileKeyboardMode' | 'timeFormat' | 'weekStart' | 'fontSize' | 'terminalFontSize' | 'editorFontSize' | 'spacing' | 'inputBarOffset' | 'mermaidRendering' | 'userMessageRendering' | 'chatRenderMode' | 'messageTransport' | 'activityRenderMode' | 'collapsibleUserMessages' | 'stickyUserHeader' | 'wideChatLayout' | 'codeBlockLineWrap' | 'splitAssistantMessageActions' | 'diffLayout' | 'mobileStatusBar' | 'dotfiles' | 'fileViewerPreview' | 'reasoning' | 'showToolFileIcons' | 'showTurnChangedFiles' | 'expandedTools' | 'followUpBehavior' | 'terminalQuickKeys' | 'fileEditorKeymap' | 'persistDraft' | 'inputSpellcheck' | 'reportUsage' | 'expandedEditorToolbar';
 
 interface OpenChamberVisualSettingsProps {
     /** Which settings to show. If undefined, shows all. */
@@ -289,6 +289,8 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
     const setFontSize = useUIStore(state => state.setFontSize);
     const terminalFontSize = useUIStore(state => state.terminalFontSize);
     const setTerminalFontSize = useUIStore(state => state.setTerminalFontSize);
+    const editorFontSize = useUIStore(state => state.editorFontSize);
+    const setEditorFontSize = useUIStore(state => state.setEditorFontSize);
     const uiFont = useUIStore(state => state.uiFont);
     const setUiFont = useUIStore(state => state.setUiFont);
     const monoFont = useUIStore(state => state.monoFont);
@@ -553,7 +555,7 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
     const hasAppearanceSettings = isVSCode
         ? hasLocalizationSettings
         : (shouldShow('theme') || showMobileLayoutSetting || shouldShow('pwaInstallName') || shouldShow('pwaOrientation') || shouldShow('timeFormat') || shouldShow('weekStart'));
-    const hasLayoutSettings = shouldShow('fontSize') || shouldShow('terminalFontSize') || shouldShow('spacing') || shouldShow('inputBarOffset');
+    const hasLayoutSettings = shouldShow('fontSize') || shouldShow('terminalFontSize') || shouldShow('editorFontSize') || shouldShow('spacing') || shouldShow('inputBarOffset');
     const hasNavigationSettings = (shouldShow('terminalQuickKeys') && !isMobile) || shouldShow('fileEditorKeymap') || shouldShow('expandedEditorToolbar');
     const hasBehaviorSettings = shouldShow('mermaidRendering')
         || shouldShow('userMessageRendering')
@@ -1253,6 +1255,35 @@ export const OpenChamberVisualSettings: React.FC<OpenChamberVisualSettingsProps>
                                 </div>
                             )}
 
+                            {shouldShow('editorFontSize') && (
+                                <div data-settings-item="appearance.editor-font-size" className={cn("py-1", isMobile ? "flex flex-col gap-3" : "flex items-center gap-8")}>
+                                    <div className={cn("flex min-w-0 flex-col", isMobile ? "w-full" : "w-56 shrink-0")}>
+                                        <span className="typography-ui-label text-foreground">{t('settings.openchamber.visual.field.editorFontSize')}</span>
+                                    </div>
+                                    <div className={cn("flex items-center gap-2", isMobile ? "w-full" : "w-fit")}>
+                                        <NumberInput
+                                            value={editorFontSize}
+                                            onValueChange={setEditorFontSize}
+                                            min={9}
+                                            max={32}
+                                            step={1}
+                                            className="w-16"
+                                        />
+                                        <Button size="sm"
+                                            type="button"
+                                            variant="ghost"
+                                            onClick={() => setEditorFontSize(13)}
+                                            disabled={editorFontSize === 13}
+                                            className="h-7 w-7 px-0 text-muted-foreground hover:text-foreground"
+                                            aria-label={t('settings.openchamber.visual.actions.resetEditorFontSizeAria')}
+                                            title={t('settings.common.actions.reset')}
+                                        >
+                                            <Icon name="restart" className="h-3.5 w-3.5" />
+                                        </Button>
+                                    </div>
+                                </div>
+                            )}
+
                             {shouldShow('spacing') && (
                                 <div data-settings-item="appearance.spacing-density" className={cn("py-1", isMobile ? "flex flex-col gap-3" : "flex items-center gap-8")}>
                                     <div className={cn("flex min-w-0 flex-col", isMobile ? "w-full" : "w-56 shrink-0")}>
diff --git a/packages/ui/src/components/sections/skills/SkillsPage.tsx b/packages/ui/src/components/sections/skills/SkillsPage.tsx
index cb43bdac..681e58a5 100644
--- a/packages/ui/src/components/sections/skills/SkillsPage.tsx
+++ b/packages/ui/src/components/sections/skills/SkillsPage.tsx
@@ -39,6 +39,7 @@ import { shikiHighlightExtension } from '@/lib/codemirror/shikiHighlight';
 import { getResolvedShikiTheme } from '@/lib/shiki/appThemeRegistry';
 import { getLanguageFromExtension } from '@/lib/toolHelpers';
 import { useThemeSystem } from '@/contexts/useThemeSystem';
+import { useUIStore } from '@/stores/useUIStore';
 import { cn } from '@/lib/utils';
 import { EditorView } from '@codemirror/view';
 import type { Extension } from '@codemirror/state';
@@ -244,22 +245,24 @@ const SkillsInstalledPage: React.FC = () => {
     loadSkillDetails();
   }, [selectedSkill, isNewSkill, selectedSkillName, skills, skillDraft, getSkillDetail]);
 
+  const editorFontSize = useUIStore((state) => state.editorFontSize);
+
   const skillEditorExtensions = React.useMemo<Extension[]>(() => {
-    const extensions: Extension[] = [createFlexokiCodeMirrorTheme(currentTheme)];
+    const extensions: Extension[] = [createFlexokiCodeMirrorTheme(currentTheme, { fontSize: editorFontSize })];
     const markdownExtension = languageByExtension(SKILL_DOCUMENT_PATH);
     if (markdownExtension) {
       extensions.push(markdownExtension);
     }
     extensions.push(EditorView.lineWrapping);
     return extensions;
-  }, [currentTheme]);
+  }, [currentTheme, editorFontSize]);
 
   const supportingFileEditorExtensions = React.useMemo<Extension[]>(() => {
     const filePath = newFileName.trim() || 'supporting-file.md';
     // Shiki token colors for code supporting files; markdown stays on lezer.
     const shikiLanguage = getLanguageFromExtension(filePath);
     const useShiki = Boolean(shikiLanguage) && shikiLanguage !== 'markdown';
-    const extensions: Extension[] = [createFlexokiCodeMirrorTheme(currentTheme, useShiki ? { syntaxColors: false } : undefined)];
+    const extensions: Extension[] = [createFlexokiCodeMirrorTheme(currentTheme, useShiki ? { syntaxColors: false, fontSize: editorFontSize } : { fontSize: editorFontSize })];
     const languageExtension = languageByExtension(filePath);
     if (languageExtension) {
       extensions.push(languageExtension);
@@ -273,7 +276,7 @@ const SkillsInstalledPage: React.FC = () => {
     }
     extensions.push(EditorView.lineWrapping);
     return extensions;
-  }, [currentTheme, newFileName]);
+  }, [currentTheme, newFileName, editorFontSize]);
 
   const handleDescriptionChange = React.useCallback((nextDescription: string) => {
     setDescription(nextDescription);
diff --git a/packages/ui/src/components/views/FilesView.tsx b/packages/ui/src/components/views/FilesView.tsx
index d788584d..1b1d0498 100644
--- a/packages/ui/src/components/views/FilesView.tsx
+++ b/packages/ui/src/components/views/FilesView.tsx
@@ -2885,17 +2885,19 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
     return () => window.removeEventListener('keydown', handleKeyDown);
   }, [canEdit, isMobile, shortcutOverrides, textViewMode]);
 
+  const editorFontSize = useUIStore((state) => state.editorFontSize);
+
   const editorExtensions = React.useMemo(() => {
     if (!selectedFile?.path) {
-      return [createFlexokiCodeMirrorTheme(currentTheme)];
+      return [createFlexokiCodeMirrorTheme(currentTheme, { fontSize: editorFontSize })];
     }
 
     // Shiki token colors (worker-backed) match the Shiki file view exactly.
     // Same language resolver as the view, so both agree on the language. When
     // Shiki is the color source, drop the lezer token colors to avoid a
-    // competing highlighter (keep the lezer language for indentation/folding).
+    // competing highlighter (Keep the lezer language for indentation/folding).
     const shikiLanguage = getLanguageFromExtension(selectedFile.path);
-    const extensions = [createFlexokiCodeMirrorTheme(currentTheme, shikiLanguage ? { syntaxColors: false } : undefined)];
+    const extensions = [createFlexokiCodeMirrorTheme(currentTheme, shikiLanguage ? { syntaxColors: false, fontSize: editorFontSize } : { fontSize: editorFontSize })];
     const language = staticLanguageExtension ?? dynamicLanguageExtension;
     if (language) {
       extensions.push(language);
@@ -2925,7 +2927,7 @@ export const FilesView: React.FC<FilesViewProps> = ({ mode = 'full' }) => {
       }));
     }
     return extensions;
-  }, [currentTheme, selectedFile?.path, staticLanguageExtension, dynamicLanguageExtension, wrapLines, isMobile, nudgeEditorSelectionAboveKeyboard]);
+  }, [currentTheme, selectedFile?.path, staticLanguageExtension, dynamicLanguageExtension, wrapLines, isMobile, nudgeEditorSelectionAboveKeyboard, editorFontSize]);
 
   const pierreTheme = React.useMemo(
     () => ({ light: lightTheme.metadata.id, dark: darkTheme.metadata.id }),
diff --git a/packages/ui/src/components/views/PlanView.tsx b/packages/ui/src/components/views/PlanView.tsx
index 1eb5cb12..045bdaea 100644
--- a/packages/ui/src/components/views/PlanView.tsx
+++ b/packages/ui/src/components/views/PlanView.tsx
@@ -345,12 +345,14 @@ export const PlanView: React.FC<PlanViewProps> = ({ targetPath = null }) => {
     };
   }, [cancel, commentText, editingDraftId, isMobile, lineSelection]);
 
+  const editorFontSize = useUIStore((state) => state.editorFontSize);
+
   const editorExtensions = React.useMemo(() => {
     // Shiki token colors only for code files; markdown keeps the lezer
     // highlighter (markdown-aware bold headings etc., and no Shiki view to match).
     const shikiLanguage = resolvedPath ? getLanguageFromExtension(resolvedPath) : null;
     const useShiki = Boolean(shikiLanguage) && shikiLanguage !== 'markdown';
-    const extensions = [createFlexokiCodeMirrorTheme(currentTheme, useShiki ? { syntaxColors: false } : undefined)];
+    const extensions = [createFlexokiCodeMirrorTheme(currentTheme, useShiki ? { syntaxColors: false, fontSize: editorFontSize } : { fontSize: editorFontSize })];
     const language = languageByExtension(resolvedPath || 'plan.md');
     if (language) {
       extensions.push(language);
@@ -364,7 +366,7 @@ export const PlanView: React.FC<PlanViewProps> = ({ targetPath = null }) => {
     }
     extensions.push(EditorView.lineWrapping);
     return extensions;
-  }, [currentTheme, resolvedPath]);
+  }, [currentTheme, resolvedPath, editorFontSize]);
 
   React.useEffect(() => {
     // Saved project plans opened via context panel should work even when session plan mode is off.
diff --git a/packages/ui/src/lib/api/types.ts b/packages/ui/src/lib/api/types.ts
index 810d849d..4cc10358 100644
--- a/packages/ui/src/lib/api/types.ts
+++ b/packages/ui/src/lib/api/types.ts
@@ -657,6 +657,7 @@ export interface SettingsPayload {
   showSplitAssistantMessageActions?: boolean;
   fontSize?: number;
   terminalFontSize?: number;
+  editorFontSize?: number;
   uiFont?: string;
   monoFont?: string;
   padding?: number;
diff --git a/packages/ui/src/lib/appearanceAutoSave.ts b/packages/ui/src/lib/appearanceAutoSave.ts
index 7ac1b1a2..3a790cb6 100644
--- a/packages/ui/src/lib/appearanceAutoSave.ts
+++ b/packages/ui/src/lib/appearanceAutoSave.ts
@@ -31,6 +31,7 @@ type AppearanceSlice = {
   sessionRetentionAction: 'archive' | 'delete';
   fontSize: number;
   terminalFontSize: number;
+  editorFontSize: number;
   uiFont: UiFontOption;
   monoFont: MonoFontOption;
   padding: number;
@@ -72,6 +73,7 @@ export const startAppearanceAutoSave = (): void => {
     sessionRetentionAction: useUIStore.getState().sessionRetentionAction,
     fontSize: useUIStore.getState().fontSize,
     terminalFontSize: useUIStore.getState().terminalFontSize,
+    editorFontSize: useUIStore.getState().editorFontSize,
     uiFont: useUIStore.getState().uiFont,
     monoFont: useUIStore.getState().monoFont,
     padding: useUIStore.getState().padding,
@@ -125,6 +127,7 @@ export const startAppearanceAutoSave = (): void => {
       sessionRetentionAction: state.sessionRetentionAction,
       fontSize: state.fontSize,
       terminalFontSize: state.terminalFontSize,
+      editorFontSize: state.editorFontSize,
       uiFont: state.uiFont,
       monoFont: state.monoFont,
       padding: state.padding,
@@ -200,6 +203,9 @@ export const startAppearanceAutoSave = (): void => {
     if (current.terminalFontSize !== previous.terminalFontSize) {
       diff.terminalFontSize = current.terminalFontSize;
     }
+    if (current.editorFontSize !== previous.editorFontSize) {
+      diff.editorFontSize = current.editorFontSize;
+    }
     if (current.uiFont !== previous.uiFont) {
       diff.uiFont = current.uiFont;
     }
diff --git a/packages/ui/src/lib/codemirror/flexokiTheme.ts b/packages/ui/src/lib/codemirror/flexokiTheme.ts
index f1acf0c5..092a4f0b 100644
--- a/packages/ui/src/lib/codemirror/flexokiTheme.ts
+++ b/packages/ui/src/lib/codemirror/flexokiTheme.ts
@@ -11,7 +11,7 @@ export function createFlexokiCodeMirrorTheme(
   // When syntax colors are provided elsewhere (e.g. the Shiki decoration
   // extension), pass `{ syntaxColors: false }` to keep only the editor UI theme
   // (gutters, selection, cursor) and avoid a competing token color source.
-  options?: { syntaxColors?: boolean },
+  options?: { syntaxColors?: boolean; fontSize?: number },
 ): Extension {
   const isDark = theme.metadata.variant === 'dark';
 
@@ -19,12 +19,14 @@ export function createFlexokiCodeMirrorTheme(
   const highlights = theme.colors.syntax.highlights || {};
   const tokens = theme.colors.syntax.tokens || {};
 
+  const contentFontSize = options?.fontSize ? `${options.fontSize}px` : 'var(--text-code)';
+
   const ui = EditorView.theme({
     '&': {
       backgroundColor: 'var(--background)',
       color: theme.colors.syntax.base.foreground,
-      fontSize: 'var(--text-code)',
-      lineHeight: '1.5rem',
+      fontSize: contentFontSize,
+      lineHeight: '1.5',
       position: 'relative' as const,
     },
     '.cm-scroller': {
diff --git a/packages/ui/src/lib/desktop.ts b/packages/ui/src/lib/desktop.ts
index 2d483992..995be684 100644
--- a/packages/ui/src/lib/desktop.ts
+++ b/packages/ui/src/lib/desktop.ts
@@ -155,6 +155,7 @@ export type DesktopSettings = {
   showSplitAssistantMessageActions?: boolean;
   fontSize?: number;
   terminalFontSize?: number;
+  editorFontSize?: number;
   uiFont?: string;
   monoFont?: string;
   padding?: number;
diff --git a/packages/ui/src/lib/i18n/messages/en.settings.ts b/packages/ui/src/lib/i18n/messages/en.settings.ts
index 8733b129..bdda7e09 100644
--- a/packages/ui/src/lib/i18n/messages/en.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/en.settings.ts
@@ -1731,10 +1731,12 @@ export const settingsDict = {
   'settings.openchamber.visual.field.fontSizePercentageAria': 'Font size percentage',
   'settings.openchamber.visual.actions.resetFontSizeAria': 'Reset font size',
   'settings.openchamber.visual.field.terminalFontSize': 'Terminal Font Size',
+  'settings.openchamber.visual.field.editorFontSize': 'Editor Font Size',
   'settings.openchamber.visual.field.codeFont': 'Code Font',
   'settings.openchamber.visual.field.selectCodeFontAria': 'Select code font',
   'settings.openchamber.visual.actions.resetCodeFontAria': 'Reset code font',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': 'Reset terminal font size',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': 'Reset editor font size',
   'settings.openchamber.visual.field.spacingDensity': 'Spacing Density',
   'settings.openchamber.visual.actions.resetSpacingAria': 'Reset spacing',
   'settings.openchamber.visual.field.inputBarOffset': 'Input Bar Offset',
diff --git a/packages/ui/src/lib/i18n/messages/es.settings.ts b/packages/ui/src/lib/i18n/messages/es.settings.ts
index 75a93be9..3e08f054 100644
--- a/packages/ui/src/lib/i18n/messages/es.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/es.settings.ts
@@ -1698,10 +1698,12 @@ export const settingsDict = {
   "settings.openchamber.visual.field.fontSizePercentageAria": "Porcentaje de tamaño de fuente",
   "settings.openchamber.visual.actions.resetFontSizeAria": "Restablecer tamaño de fuente",
   "settings.openchamber.visual.field.terminalFontSize": "Tamaño de fuente del terminal",
+  "settings.openchamber.visual.field.editorFontSize": "Tamaño de fuente del editor",
   "settings.openchamber.visual.field.codeFont": "Fuente de código",
   "settings.openchamber.visual.field.selectCodeFontAria": "Seleccionar fuente de código",
   "settings.openchamber.visual.actions.resetCodeFontAria": "Restablecer fuente de código",
   "settings.openchamber.visual.actions.resetTerminalFontSizeAria": "Restablecer tamaño de fuente del terminal",
+  "settings.openchamber.visual.actions.resetEditorFontSizeAria": "Restablecer tamaño de fuente del editor",
   "settings.openchamber.visual.field.spacingDensity": "Densidad de espaciado",
   "settings.openchamber.visual.actions.resetSpacingAria": "Restablecer espaciado",
   "settings.openchamber.visual.field.inputBarOffset": "Desplazamiento de la barra de entrada",
diff --git a/packages/ui/src/lib/i18n/messages/fr.settings.ts b/packages/ui/src/lib/i18n/messages/fr.settings.ts
index b3603c35..41da4d97 100644
--- a/packages/ui/src/lib/i18n/messages/fr.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/fr.settings.ts
@@ -1613,10 +1613,12 @@ export const settingsDict = {
   'settings.openchamber.visual.field.fontSizePercentageAria': 'Pourcentage de taille de police',
   'settings.openchamber.visual.actions.resetFontSizeAria': 'Réinitialiser la taille de la police',
   'settings.openchamber.visual.field.terminalFontSize': 'Taille de la police du terminal',
+  'settings.openchamber.visual.field.editorFontSize': 'Taille de la police de l\'éditeur',
   'settings.openchamber.visual.field.codeFont': 'Police de code',
   'settings.openchamber.visual.field.selectCodeFontAria': 'Sélectionnez la police du code',
   'settings.openchamber.visual.actions.resetCodeFontAria': 'Réinitialiser la police du code',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': 'Réinitialiser la taille de la police du terminal',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': 'Réinitialiser la taille de la police de l\'éditeur',
   'settings.openchamber.visual.field.spacingDensity': 'Densité d\'espacement',
   'settings.openchamber.visual.actions.resetSpacingAria': 'Réinitialiser l\'espacement',
   'settings.openchamber.visual.field.inputBarOffset': 'Décalage de la barre d\'entrée',
diff --git a/packages/ui/src/lib/i18n/messages/ja.settings.ts b/packages/ui/src/lib/i18n/messages/ja.settings.ts
index 40cd2e0e..7ac9f7c6 100644
--- a/packages/ui/src/lib/i18n/messages/ja.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/ja.settings.ts
@@ -1731,10 +1731,12 @@ export const settingsDict = {
   'settings.openchamber.visual.field.fontSizePercentageAria': 'フォントサイズの割合',
   'settings.openchamber.visual.actions.resetFontSizeAria': 'フォントサイズをリセット',
   'settings.openchamber.visual.field.terminalFontSize': 'ターミナルフォントサイズ',
+  'settings.openchamber.visual.field.editorFontSize': 'エディターフォントサイズ',
   'settings.openchamber.visual.field.codeFont': 'コードフォント',
   'settings.openchamber.visual.field.selectCodeFontAria': 'コードフォントを選択',
   'settings.openchamber.visual.actions.resetCodeFontAria': 'コードフォントをリセット',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': 'ターミナルフォントサイズをリセット',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': 'エディターフォントサイズをリセット',
   'settings.openchamber.visual.field.spacingDensity': '間隔の密度',
   'settings.openchamber.visual.actions.resetSpacingAria': '間隔をリセット',
   'settings.openchamber.visual.field.inputBarOffset': '入力バーオフセット',
diff --git a/packages/ui/src/lib/i18n/messages/ko.settings.ts b/packages/ui/src/lib/i18n/messages/ko.settings.ts
index 9aceeaf7..f5b5472c 100644
--- a/packages/ui/src/lib/i18n/messages/ko.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/ko.settings.ts
@@ -1698,10 +1698,12 @@ export const settingsDict = {
   'settings.openchamber.visual.field.fontSizePercentageAria': '폰트 크기 비율',
   'settings.openchamber.visual.actions.resetFontSizeAria': '폰트 크기 초기화',
   'settings.openchamber.visual.field.terminalFontSize': '터미널 폰트 크기',
+  'settings.openchamber.visual.field.editorFontSize': '에디터 폰트 크기',
   'settings.openchamber.visual.field.codeFont': '코드 폰트',
   'settings.openchamber.visual.field.selectCodeFontAria': '코드 폰트 선택',
   'settings.openchamber.visual.actions.resetCodeFontAria': '코드 폰트 초기화',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': '터미널 폰트 크기 초기화',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': '에디터 폰트 크기 초기화',
   'settings.openchamber.visual.field.spacingDensity': '간격 밀도',
   'settings.openchamber.visual.actions.resetSpacingAria': '간격 초기화',
   'settings.openchamber.visual.field.inputBarOffset': '입력 바 오프셋',
diff --git a/packages/ui/src/lib/i18n/messages/pl.settings.ts b/packages/ui/src/lib/i18n/messages/pl.settings.ts
index acdecd69..43ed887e 100644
--- a/packages/ui/src/lib/i18n/messages/pl.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/pl.settings.ts
@@ -935,6 +935,7 @@ export const settingsDict = {
   'settings.openchamber.visual.actions.resetInterfaceFontAria': 'Zresetuj czcionkę interfejsu',
   'settings.openchamber.visual.actions.resetSpacingAria': 'Zresetuj odstępy',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': 'Zresetuj rozmiar czcionki terminala',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': 'Zresetuj rozmiar czcionki edytora',
   'settings.openchamber.visual.field.activityDefaultModeAria': 'Domyślny tryb aktywności: {option}',
   'settings.openchamber.visual.field.bash': 'Bash',
   'settings.openchamber.visual.field.codeFont': 'Czcionka kodu',
@@ -1004,6 +1005,7 @@ export const settingsDict = {
   'settings.openchamber.visual.field.expandedEditorToolbarAria': 'Always show editor toolbar',
   'settings.openchamber.visual.field.expandedEditorToolbar': 'Always show editor toolbar (docked under the file tabs)',
   'settings.openchamber.visual.field.terminalFontSize': 'Rozmiar czcionki terminala',
+  'settings.openchamber.visual.field.editorFontSize': 'Rozmiar czcionki edytora',
   'settings.openchamber.visual.field.terminalQuickKeys': 'Szybkie klawisze terminala',
   'settings.openchamber.visual.field.terminalQuickKeysAria': 'Szybkie klawisze terminala',
   'settings.openchamber.visual.field.terminalQuickKeysTooltip': 'Pokaż Esc, Ctrl i strzałki w widoku terminala',
diff --git a/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts b/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts
index ea273353..f408211d 100644
--- a/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/pt-BR.settings.ts
@@ -1698,10 +1698,12 @@ export const settingsDict = {
   "settings.openchamber.visual.field.fontSizePercentageAria": "Porcentagem do tamanho base",
   "settings.openchamber.visual.actions.resetFontSizeAria": "Redefinir tamanho base",
   "settings.openchamber.visual.field.terminalFontSize": "Tamanho base do terminal",
+  "settings.openchamber.visual.field.editorFontSize": "Tamanho base do editor",
   "settings.openchamber.visual.field.codeFont": "Fonte do código",
   "settings.openchamber.visual.field.selectCodeFontAria": "Selecionar fonte do código",
   "settings.openchamber.visual.actions.resetCodeFontAria": "Redefinir fonte do código",
   "settings.openchamber.visual.actions.resetTerminalFontSizeAria": "Redefinir tamanho base do terminal",
+  "settings.openchamber.visual.actions.resetEditorFontSizeAria": "Redefinir tamanho base do editor",
   "settings.openchamber.visual.field.spacingDensity": "Densidade de espaçamento",
   "settings.openchamber.visual.actions.resetSpacingAria": "Redefinir espaçamento",
   "settings.openchamber.visual.field.inputBarOffset": "Deslocamento da barra de entrada",
diff --git a/packages/ui/src/lib/i18n/messages/uk.settings.ts b/packages/ui/src/lib/i18n/messages/uk.settings.ts
index 8bca1b7d..fc54aa55 100644
--- a/packages/ui/src/lib/i18n/messages/uk.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/uk.settings.ts
@@ -1698,10 +1698,12 @@ export const settingsDict = {
   "settings.openchamber.visual.field.fontSizePercentageAria": "Розмір шрифту у відсотках",
   "settings.openchamber.visual.actions.resetFontSizeAria": "Скинути розмір шрифту",
   "settings.openchamber.visual.field.terminalFontSize": "Розмір шрифту терміналу",
+  "settings.openchamber.visual.field.editorFontSize": "Розмір шрифту редактора",
   "settings.openchamber.visual.field.codeFont": "Шрифт коду",
   "settings.openchamber.visual.field.selectCodeFontAria": "Вибрати шрифт коду",
   "settings.openchamber.visual.actions.resetCodeFontAria": "Скинути шрифт коду",
   "settings.openchamber.visual.actions.resetTerminalFontSizeAria": "Скинути розмір шрифту терміналу",
+  "settings.openchamber.visual.actions.resetEditorFontSizeAria": "Скинути розмір шрифту редактора",
   "settings.openchamber.visual.field.spacingDensity": "Щільність інтервалу",
   "settings.openchamber.visual.actions.resetSpacingAria": "Скинути інтервал",
   "settings.openchamber.visual.field.inputBarOffset": "Зміщення панелі вводу",
diff --git a/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts b/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts
index 28ba6c53..d0e8059e 100644
--- a/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-CN.settings.ts
@@ -1698,10 +1698,12 @@ export const settingsDict = {
   'settings.openchamber.visual.field.fontSizePercentageAria': '字体大小百分比',
   'settings.openchamber.visual.actions.resetFontSizeAria': '重置字体大小',
   'settings.openchamber.visual.field.terminalFontSize': '终端字体大小',
+  'settings.openchamber.visual.field.editorFontSize': '编辑器字体大小',
   'settings.openchamber.visual.field.codeFont': '代码字体',
   'settings.openchamber.visual.field.selectCodeFontAria': '选择代码字体',
   'settings.openchamber.visual.actions.resetCodeFontAria': '重置代码字体',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': '重置终端字体大小',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': '重置编辑器字体大小',
   'settings.openchamber.visual.field.spacingDensity': '间距密度',
   'settings.openchamber.visual.actions.resetSpacingAria': '重置间距',
   'settings.openchamber.visual.field.inputBarOffset': '输入栏偏移',
diff --git a/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts b/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts
index 999e545d..e519f5e2 100644
--- a/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts
+++ b/packages/ui/src/lib/i18n/messages/zh-TW.settings.ts
@@ -1609,10 +1609,12 @@
   'settings.openchamber.visual.field.fontSizePercentageAria': '字體大小百分比',
   'settings.openchamber.visual.actions.resetFontSizeAria': '重設字體大小',
   'settings.openchamber.visual.field.terminalFontSize': '終端機字體大小',
+  'settings.openchamber.visual.field.editorFontSize': '編輯器字體大小',
   'settings.openchamber.visual.field.codeFont': '程式碼字體',
   'settings.openchamber.visual.field.selectCodeFontAria': '選擇程式碼字體',
   'settings.openchamber.visual.actions.resetCodeFontAria': '重設程式碼字體',
   'settings.openchamber.visual.actions.resetTerminalFontSizeAria': '重設終端機字體大小',
+  'settings.openchamber.visual.actions.resetEditorFontSizeAria': '重設編輯器字體大小',
   'settings.openchamber.visual.field.spacingDensity': '間距密度',
   'settings.openchamber.visual.actions.resetSpacingAria': '重設間距',
   'settings.openchamber.visual.field.inputBarOffset': '輸入列偏移',
diff --git a/packages/ui/src/lib/persistence.ts b/packages/ui/src/lib/persistence.ts
index 02afee54..27a399b7 100644
--- a/packages/ui/src/lib/persistence.ts
+++ b/packages/ui/src/lib/persistence.ts
@@ -594,6 +594,9 @@ const applyDesktopUiPreferences = (settings: DesktopSettings) => {
   if (typeof settings.terminalFontSize === 'number' && Number.isFinite(settings.terminalFontSize) && settings.terminalFontSize !== store.terminalFontSize) {
     store.setTerminalFontSize(settings.terminalFontSize);
   }
+  if (typeof settings.editorFontSize === 'number' && Number.isFinite(settings.editorFontSize) && settings.editorFontSize !== store.editorFontSize) {
+    store.setEditorFontSize(settings.editorFontSize);
+  }
   if (isUiFontOption(settings.uiFont) && settings.uiFont !== store.uiFont) {
     store.setUiFont(settings.uiFont);
   }
@@ -1111,6 +1114,9 @@ const sanitizeWebSettings = (payload: unknown): DesktopSettings | null => {
   if (typeof candidate.terminalFontSize === 'number' && Number.isFinite(candidate.terminalFontSize)) {
     result.terminalFontSize = candidate.terminalFontSize;
   }
+  if (typeof candidate.editorFontSize === 'number' && Number.isFinite(candidate.editorFontSize)) {
+    result.editorFontSize = candidate.editorFontSize;
+  }
   if (isUiFontOption(candidate.uiFont)) {
     result.uiFont = candidate.uiFont;
   }
diff --git a/packages/ui/src/lib/settings/search.ts b/packages/ui/src/lib/settings/search.ts
index f25486ce..3d61b1a4 100644
--- a/packages/ui/src/lib/settings/search.ts
+++ b/packages/ui/src/lib/settings/search.ts
@@ -116,6 +116,12 @@ const SETTINGS_SEARCH_ITEMS: readonly SettingsSearchItem[] = [
     titleKey: 'settings.openchamber.visual.field.terminalFontSize',
     keywords: ['terminal', 'font', 'text size'],
   },
+  {
+    id: 'appearance.editor-font-size',
+    page: 'appearance',
+    titleKey: 'settings.openchamber.visual.field.editorFontSize',
+    keywords: ['editor', 'font', 'text size', 'code'],
+  },
   {
     id: 'appearance.spacing-density',
     page: 'appearance',
diff --git a/packages/ui/src/stores/useUIStore.ts b/packages/ui/src/stores/useUIStore.ts
index 8bba2be3..47944e83 100644
--- a/packages/ui/src/stores/useUIStore.ts
+++ b/packages/ui/src/stores/useUIStore.ts
@@ -587,6 +587,7 @@ interface UIStore {
   // Global draft welcome starters; null = unset (use the default built-in set).
   globalDraftStarters: DraftStarterRef[] | null;
   terminalFontSize: number;
+  editorFontSize: number;
   uiFont: UiFontOption;
   monoFont: MonoFontOption;
   padding: number;
@@ -736,6 +737,7 @@ interface UIStore {
   setFontSize: (size: number) => void;
   setGlobalDraftStarters: (refs: DraftStarterRef[]) => void;
   setTerminalFontSize: (size: number) => void;
+  setEditorFontSize: (size: number) => void;
   setUiFont: (font: UiFontOption) => void;
   setMonoFont: (font: MonoFontOption) => void;
   setPadding: (size: number) => void;
@@ -883,6 +885,7 @@ export const useUIStore = create<UIStore>()(
         fontSize: 100,
         globalDraftStarters: null,
         terminalFontSize: 13,
+        editorFontSize: 13,
         uiFont: DEFAULT_UI_FONT,
         monoFont: DEFAULT_MONO_FONT,
         padding: 100,
@@ -1633,6 +1636,12 @@ export const useUIStore = create<UIStore>()(
           set({ terminalFontSize: clamped });
         },
 
+        setEditorFontSize: (size) => {
+          const rounded = Math.round(size);
+          const clamped = Math.max(9, Math.min(32, rounded));
+          set({ editorFontSize: clamped });
+        },
+
         setUiFont: (font) => {
           set({ uiFont: font });
         },
@@ -2279,6 +2288,7 @@ export const useUIStore = create<UIStore>()(
           fontSize: state.fontSize,
           globalDraftStarters: state.globalDraftStarters,
           terminalFontSize: state.terminalFontSize,
+          editorFontSize: state.editorFontSize,
           uiFont: state.uiFont,
           monoFont: state.monoFont,
           padding: state.padding,