diff --git a/src/browser/components/preferences/zen-settings.js b/src/browser/components/preferences/zen-settings.js
index bd5385f5..d871e169 100644
--- a/src/browser/components/preferences/zen-settings.js
+++ b/src/browser/components/preferences/zen-settings.js
@@ -108,7 +108,6 @@ var gZenMarketplaceManager = {
   },
 
   async observe() {
-    ZenThemesCommon.resetThemesCache();
     await this._buildThemesList();
   },
 
diff --git a/src/zen/mods/ZenThemesCommon.mjs b/src/zen/mods/ZenThemesCommon.mjs
index f8bda8cf..82632939 100644
--- a/src/zen/mods/ZenThemesCommon.mjs
+++ b/src/zen/mods/ZenThemesCommon.mjs
@@ -36,35 +36,27 @@ var ZenThemesCommon = {
     return PathUtils.join(this.themesRootPath, themeId);
   },
 
-  resetThemesCache() {
-    this.themes = null;
-  },
-
   async getThemes() {
-    if (!this.themes) {
-      if (!(await IOUtils.exists(this.themesDataFile))) {
-        await IOUtils.writeJSON(this.themesDataFile, {});
-      }
-
-      try {
-        this.themes = await IOUtils.readJSON(this.themesDataFile);
-      } catch (e) {
-        // If we have a corrupted file, reset it
-        await IOUtils.writeJSON(this.themesDataFile, {});
-        this.themes = {};
-        gNotificationBox.appendNotification(
-          'zen-themes-corrupted',
-          {
-            label: { 'l10n-id': 'zen-themes-corrupted' },
-            image: 'chrome://browser/skin/notification-icons/persistent-storage-blocked.svg',
-            priority: gNotificationBox.PRIORITY_WARNING_HIGH,
-          },
-          []
-        );
-      }
+    if (!(await IOUtils.exists(this.themesDataFile))) {
+      await IOUtils.writeJSON(this.themesDataFile, {});
     }
 
-    return this.themes;
+    let themes = {};
+    try {
+      themes = await IOUtils.readJSON(this.themesDataFile);
+      if (themes === null || typeof themes !== 'object') {
+        throw new Error('Themes data file is null');
+      }
+    } catch (e) {
+      // If we have a corrupted file, reset it
+      await IOUtils.writeJSON(this.themesDataFile, {});
+      Services.wm
+        .getMostRecentWindow('navigator:browser')
+        .gZenUIManager.showToast('zen-themes-corrupted', {
+          timeout: 8000,
+        });
+    }
+    return themes;
   },
 
   async getThemePreferences(theme) {
diff --git a/src/zen/mods/ZenThemesImporter.mjs b/src/zen/mods/ZenThemesImporter.mjs
index 1303db5f..e1378a56 100644
--- a/src/zen/mods/ZenThemesImporter.mjs
+++ b/src/zen/mods/ZenThemesImporter.mjs
@@ -63,6 +63,7 @@ var gZenThemesImporter = new (class {
           return;
         }
 
+        await ZenThemesCommon.getThemes(); // Check for any errors in the themes data file
         const themes = await this.getEnabledThemes();
 
         const themesWithPreferences = await Promise.all(
@@ -159,8 +160,6 @@ var gZenThemesImporter = new (class {
   }
 
   async rebuildThemeStylesheet() {
-    ZenThemesCommon.themes = null;
-
     await this.removeStylesheet();
 
     const themes = await this.getEnabledThemes();
@@ -316,7 +315,6 @@ var gZenThemesImporter = new (class {
 
   async writeStylesheet(themeList = []) {
     const themes = [];
-    ZenThemesCommon.themes = null;
 
     for (let theme of themeList) {
       theme._chromeURL = this.getStylesheetURIForTheme(theme).spec;
diff --git a/src/zen/mods/actors/ZenThemeMarketplaceParent.sys.mjs b/src/zen/mods/actors/ZenThemeMarketplaceParent.sys.mjs
index c26f4446..1a6efa5a 100644
--- a/src/zen/mods/actors/ZenThemeMarketplaceParent.sys.mjs
+++ b/src/zen/mods/actors/ZenThemeMarketplaceParent.sys.mjs
@@ -75,8 +75,7 @@ export class ZenThemeMarketplaceParent extends JSWindowActorParent {
     console.info('ZenThemeMarketplaceParent: Checking for theme updates');
 
     let updates = [];
-    this._themes = null;
-
+    const themes = await this.getThemes();
     for (const theme of Object.values(await this.getThemes())) {
       try {
         const themeInfo = await this.sendQuery('ZenThemeMarketplace:GetThemeInfo', {
@@ -102,15 +101,14 @@ export class ZenThemeMarketplaceParent extends JSWindowActorParent {
           updates.push(themeInfo);
 
           await this.removeTheme(theme.id, false);
-
-          this._themes[themeInfo.id] = themeInfo;
+          themes[themeInfo.id] = themeInfo;
         }
       } catch (e) {
         console.error('ZenThemeMarketplaceParent: Error checking for theme updates', e);
       }
     }
 
-    await this.updateThemes(this._themes);
+    await this.updateThemes(themes);
 
     this.sendAsyncMessage('ZenThemeMarketplace:CheckForUpdatesFinished', { updates });
   }
@@ -123,8 +121,10 @@ export class ZenThemeMarketplaceParent extends JSWindowActorParent {
     return await IOUtils.readJSON(this.themesDataFile);
   }
 
-  async updateThemes(themes) {
-    this._themes = themes;
+  async updateThemes(themes = undefined) {
+    if (!themes) {
+      themes = await this.getThemes();
+    }
     await IOUtils.writeJSON(this.themesDataFile, themes);
     await this.checkForThemeChanges();
   }