diff --git a/src/components/ha-icon.ts b/src/components/ha-icon.ts
index 7f1bfc57c9..7a8eee1896 100644
--- a/src/components/ha-icon.ts
+++ b/src/components/ha-icon.ts
@@ -90,7 +90,14 @@ export class HaIcon extends LitElement {
       return;
     }
 
-    const databaseIcon: string = await getIcon(iconName);
+    let databaseIcon: string | undefined;
+    try {
+      databaseIcon = await getIcon(iconName);
+    } catch (_err) {
+      // Firefox in private mode doesn't support IDB
+      databaseIcon = undefined;
+    }
+
     if (databaseIcon) {
       this._path = databaseIcon;
       cachedIcons[iconName] = databaseIcon;
diff --git a/src/data/iconsets.ts b/src/data/iconsets.ts
index 1f28e7dd80..941f84cd74 100644
--- a/src/data/iconsets.ts
+++ b/src/data/iconsets.ts
@@ -14,12 +14,12 @@ export const iconStore = new Store("hass-icon-db", "mdi-icon-store");
 
 export const MDI_PREFIXES = ["mdi", "hass", "hassio", "hademo"];
 
-let toRead: Array<[string, (string) => void]> = [];
+let toRead: Array<[string, (string) => void, () => void]> = [];
 
 // Queue up as many icon fetches in 1 transaction
 export const getIcon = (iconName: string) =>
-  new Promise<string>((resolve) => {
-    toRead.push([iconName, resolve]);
+  new Promise<string>((resolve, reject) => {
+    toRead.push([iconName, resolve, reject]);
 
     if (toRead.length > 1) {
       return;
@@ -38,6 +38,13 @@ export const getIcon = (iconName: string) =>
         for (const [resolve_, request] of results) {
           resolve_(request.result);
         }
+      })
+      .catch(() => {
+        // Firefox in private mode doesn't support IDB
+        for (const [, , reject_] of toRead) {
+          reject_();
+        }
+        toRead = [];
       });
   });
 
diff --git a/src/panels/lovelace/cards/hui-markdown-card.ts b/src/panels/lovelace/cards/hui-markdown-card.ts
index 54f6d3fda2..475531c578 100644
--- a/src/panels/lovelace/cards/hui-markdown-card.ts
+++ b/src/panels/lovelace/cards/hui-markdown-card.ts
@@ -136,7 +136,7 @@ export class HuiMarkdownCard extends LitElement implements LovelaceCard {
           },
         }
       );
-    } catch {
+    } catch (_err) {
       this._content = this._config!.content;
       this._unsubRenderTemplate = undefined;
     }