diff --git a/docfiles/themes/high-contrast.json b/docfiles/themes/high-contrast.json
index 1d2988768a44..75bbab116a2e 100644
--- a/docfiles/themes/high-contrast.json
+++ b/docfiles/themes/high-contrast.json
@@ -1,6 +1,7 @@
 {
     "id": "high-contrast",
     "name": "High Contrast",
+    "monacoBaseTheme": "hc-black",
     "overrideFiles": [
         "/docfiles/themes/overrides/high-contrast-overrides.css"
     ],
diff --git a/react-common/components/theming/themeManager.ts b/react-common/components/theming/themeManager.ts
index acde0ea5c80d..42a30636d1c5 100644
--- a/react-common/components/theming/themeManager.ts
+++ b/react-common/components/theming/themeManager.ts
@@ -2,9 +2,15 @@ export interface ThemeInfo {
     id: string;
     name: string;
     overrides?: string;
+    monacoBaseTheme?: string; // https://code.visualstudio.com/docs/getstarted/themes
     colors: { [key: string]: string };
 }
 
+export interface ThemeChangeSubscriber {
+    subscriberId: string;
+    onThemeChange: () => void;
+}
+
 /*
  * Singleton class to handle theming operations, like loading and switching themes.
 */
@@ -12,6 +18,7 @@ export class ThemeManager {
     private static instance: ThemeManager;
     private themes: ThemeInfo[];
     private activeTheme: ThemeInfo;
+    private subscribers: ThemeChangeSubscriber[];
 
     private constructor() {} // private to ensure singleton
 
@@ -46,6 +53,7 @@ export class ThemeManager {
             const theme: ThemeInfo = {
                 id: themeData.id,
                 name: themeData.name,
+                monacoBaseTheme: themeData.monacoBaseTheme,
                 colors: themeData.colors
             };
 
@@ -68,8 +76,8 @@ export class ThemeManager {
         }
     }
 
-    public getActiveThemeId(): string {
-        return this.activeTheme?.id;
+    public getActiveTheme(): Readonly<ThemeInfo> {
+        return this.activeTheme;
     }
 
     public async getAllThemes(): Promise<ThemeInfo[]> {
@@ -81,7 +89,7 @@ export class ThemeManager {
     }
     
     public async switchTheme(themeId: string) {
-        if (themeId === this.getActiveThemeId()) {
+        if (themeId === this.getActiveTheme()?.id) {
             return;
         }
 
@@ -103,7 +111,30 @@ export class ThemeManager {
 
             // textContent is safer than innerHTML, less vulnerable to XSS
             styleElement.textContent = `.pxt-theme-root { ${themeAsStyle} }`;
+
+            this.activeTheme = theme;
+            this.notifySubscribers();
+        }
+    }
+
+    public subscribe(subscriberId: string, onThemeChange: () => void) {
+        if (this.subscribers?.some(s => s.subscriberId === subscriberId)) {
+            return;
         }
+
+        if (!this.subscribers) {
+            this.subscribers = [];
+        }
+
+        this.subscribers.push({ subscriberId, onThemeChange });
+    }
+
+    public unsubscribe(subscriberId: string) {
+        this.subscribers = this.subscribers.filter(s => s.subscriberId !== subscriberId);
+    }
+
+    private notifySubscribers() {
+        this.subscribers.forEach(s => s.onThemeChange());
     }
 }
 
diff --git a/theme/monaco.less b/theme/monaco.less
index b637ed130fe4..f6678a858046 100644
--- a/theme/monaco.less
+++ b/theme/monaco.less
@@ -32,23 +32,33 @@
         Monaco Editor
 *******************************/
 
+.monaco-editor {
+    background-color: var(--pxt-target-background1) !important;
+    color: var(--pxt-target-foreground1) !important;
+
+    .monaco-editor-background, .margin {
+        background-color: var(--pxt-target-background1) !important;
+        color: var(--pxt-target-foreground1) !important;
+    }
+}
+
 .monaco-editor .monaco-scrollable-element.editor-scrollable {
     margin-left: .5rem;
 }
 
 /* Monaco Editor Line number colors, changed from the default light theme */
 .monaco-editor.vs .line-numbers {
-    color: #2c3e50 !important;
+    color: var(--pxt-target-foreground1) !important;
 }
 
 /* Monaco Editor Line number background, changed from the default light theme */
 .monaco-editor.vs .margin-view-overlays.monaco-editor-background {
-    background: rgba(0, 0, 0, 0.05) !important;
+    background: var(--pxt-neutral-alpha05) !important;
 }
 
 /* Monaco Editor Current line highlighting, only needed for the light theme */
 .monaco-editor.vs .current-line {
-	background: rgba(0, 0, 255, 0.1) !important;
+	background: var(--pxt-colors-blue-alpha10) !important;
 }
 
 /* Monaco Editor Suggest Widget, styling */
@@ -57,17 +67,17 @@
     z-index: @monacoSuggestZIndex !important;
 }
 .monaco-list-row.focused {
-    background-color:#0078D7 !important;
-    color: #fff !important;
+    background-color: var(--pxt-colors-blue-background) !important;
+    color: var(--pxt-colors-blue-foreground) !important;
 }
 .monaco-editor.vs .suggest-widget:not(.frozen) .monaco-list .monaco-list-row .monaco-highlighted-label .highlight {
-    color: #0078D7 !important;
+    color: var(--pxt-colors-blue-background) !important;
 }
 .monaco-editor.vs .suggest-widget:not(.frozen) .monaco-list .monaco-list-row.focused .monaco-highlighted-label .highlight {
-    color: #fff !important;
+    color: var(--pxt-colors-blue-foreground) !important;
 }
 .monaco-editor.vs .suggest-widget .details > .monaco-scrollable-element > .body > .type, .monaco-editor .suggest-widget .monaco-list .monaco-list-row .type-label {
-    color: #FFB900 !important;
+    color: var(--pxt-colors-orange-background) !important;
 }
 
 /* Monaco Editor Rename Widget: default positioning causes scroll with transparent editor toolbar, so we reposition */
@@ -82,8 +92,8 @@
 
 /* Monaco Editor Main tokens */
 .monaco-editor .highlight-statement {
-    background-color: #b8b8fd;
-    color: black !important;
+    background-color: var(--pxt-target-background-hover1);
+    color: var(--pxt-target-foreground-hover1) !important;
 }
 
 /* Monaco Toolbox */
diff --git a/webapp/src/app.tsx b/webapp/src/app.tsx
index 0423566a089f..0bfe159c09be 100644
--- a/webapp/src/app.tsx
+++ b/webapp/src/app.tsx
@@ -6197,7 +6197,7 @@ document.addEventListener("DOMContentLoaded", async () => {
             const defaultColorThemeId = pxt.appTarget?.appTheme?.defaultColorTheme;
             if (defaultColorThemeId) {
                 const themeManager = ThemeManager.getInstance();
-                if (defaultColorThemeId !== themeManager.getActiveThemeId()) {
+                if (defaultColorThemeId !== themeManager.getActiveTheme()?.id) {
                     return themeManager.switchTheme(defaultColorThemeId);
                 }
             }
diff --git a/webapp/src/monaco.tsx b/webapp/src/monaco.tsx
index 01177842f525..c018e880c209 100644
--- a/webapp/src/monaco.tsx
+++ b/webapp/src/monaco.tsx
@@ -30,6 +30,7 @@ import IProjectView = pxt.editor.IProjectView;
 import ErrorListState = pxt.editor.ErrorListState;
 
 import * as pxtblockly from "../../pxtblocks";
+import { ThemeChangeSubscriber, ThemeManager } from "../../react-common/components/theming/themeManager";
 
 const MIN_EDITOR_FONT_SIZE = 10
 const MAX_EDITOR_FONT_SIZE = 40
@@ -390,6 +391,8 @@ export class Editor extends toolboxeditor.ToolboxEditor {
         this.onUserPreferencesChanged = this.onUserPreferencesChanged.bind(this);
 
         data.subscribe(this.userPreferencesSubscriber, auth.HIGHCONTRAST);
+
+        ThemeManager.getInstance()?.subscribe("monaco", () => this.onUserPreferencesChanged());
     }
 
     onUserPreferencesChanged() {
@@ -747,8 +750,11 @@ export class Editor extends toolboxeditor.ToolboxEditor {
         }
 
         const colors = pxt.appTarget.appTheme.monacoColors || {};
+        const baseTheme: monaco.editor.BuiltinTheme = hc
+            ? "hc-black"
+            : (ThemeManager.getInstance()?.getActiveTheme()?.monacoBaseTheme as monaco.editor.BuiltinTheme) ?? (inverted ? "vs-dark" : "vs");
         monaco.editor.defineTheme('pxtTheme', {
-            base: hc ? 'hc-black' : (inverted ? 'vs-dark' : 'vs'), // can also be vs-dark or hc-black
+            base: baseTheme,
             inherit: true, // can also be false to completely replace the builtin rules
             rules: rules,
             colors: hc ? {} : colors
@@ -2109,15 +2115,9 @@ export class Editor extends toolboxeditor.ToolboxEditor {
     }
 
     protected getEditorColor() {
-        if (pxt.appTarget.appTheme.monacoColors && pxt.appTarget.appTheme.monacoColors["editor.background"]) {
-            return pxt.appTarget.appTheme.monacoColors["editor.background"]
-        }
-        else if (pxt.appTarget.appTheme.invertedMonaco) {
-            return "#1e1e1e"
-        }
-        else {
-            return "#ffffff"
-        }
+        // Editor color is set to var(--pxt-target-background1), which can change.
+        // This is not ideal, but just return empty for now.
+        return "";
     }
 }