diff --git a/js/services/hashtagPreferencesHelpers.js b/js/services/hashtagPreferencesHelpers.js
new file mode 100644
index 00000000..78ea50b3
--- /dev/null
+++ b/js/services/hashtagPreferencesHelpers.js
@@ -0,0 +1,72 @@
+// js/services/hashtagPreferencesHelpers.js
+//
+// Pure helpers extracted from hashtagPreferencesService.js to keep that service
+// under the file-size budget. No module state — safe to test in isolation.
+
+import { HEX64_REGEX } from "../utils/hex.js";
+
+const MAX_DECRYPT_RETRY_DELAY_MS = 60000;
+
+// Transient decrypt failures that must RETRY in the background rather than give
+// up: our own timeout, a severed nip-07 message port ("message channel closed"),
+// and the circuit breaker's fast-fail. Without this a brief channel drop during
+// the login burst abandons hashtag prefs until a refresh (KNOWN_BUGS #0).
+const TRANSIENT_DECRYPT_ERROR_CODES = new Set([
+  "hashtag-preferences-decrypt-timeout",
+  "nip07-channel-unresponsive",
+]);
+const TRANSIENT_DECRYPT_MESSAGE_PATTERNS = [
+  "message channel closed",
+  "could not establish connection",
+  "receiving end does not exist",
+  "extension context invalidated",
+  "connection lost",
+  "channel is unresponsive",
+];
+
+export function isTransientDecryptError(error) {
+  if (!error) return false;
+  if (error.code && TRANSIENT_DECRYPT_ERROR_CODES.has(error.code)) return true;
+  const message =
+    typeof error.message === "string" ? error.message.toLowerCase() : "";
+  if (TRANSIENT_DECRYPT_MESSAGE_PATTERNS.some((p) => message.includes(p))) {
+    return true;
+  }
+  // decryptEvent wraps the per-scheme Promise.any failures in a generic
+  // "decrypt-failed" error and nests the real causes under .errors/.cause —
+  // recurse so a channel-death sub-error still triggers a retry.
+  const nested = Array.isArray(error.errors)
+    ? error.errors
+    : Array.isArray(error.cause)
+      ? error.cause
+      : null;
+  if (nested) {
+    return nested.some((entry) => isTransientDecryptError(entry?.error || entry));
+  }
+  return false;
+}
+
+export function computeRetryDelay(baseDelayMs, attempt) {
+  const normalizedAttempt =
+    Number.isFinite(attempt) && attempt > 0 ? Math.floor(attempt) : 0;
+  const multiplier = 2 ** normalizedAttempt;
+  const nextDelay = Math.max(250, Math.floor(baseDelayMs * multiplier));
+  return Math.min(MAX_DECRYPT_RETRY_DELAY_MS, nextDelay);
+}
+
+export function normalizeHexPubkey(pubkey) {
+  if (typeof pubkey !== "string") {
+    return null;
+  }
+
+  const trimmed = pubkey.trim();
+  if (!trimmed) {
+    return null;
+  }
+
+  if (HEX64_REGEX.test(trimmed)) {
+    return trimmed.toLowerCase();
+  }
+
+  return null;
+}
diff --git a/js/services/hashtagPreferencesService.js b/js/services/hashtagPreferencesService.js
index 5ebbbba1..ef85233f 100644
--- a/js/services/hashtagPreferencesService.js
+++ b/js/services/hashtagPreferencesService.js
@@ -39,7 +39,11 @@ import {
   computeIncrementalSinceWithOverlap,
   selectNewestListEvent,
 } from "../nostr/listEventOrdering.js";
-import { HEX64_REGEX } from "../utils/hex.js";
+import {
+  isTransientDecryptError,
+  computeRetryDelay,
+  normalizeHexPubkey,
+} from "./hashtagPreferencesHelpers.js";
 import { SHORT_TIMEOUT_MS, NETWORK_RETRY_DELAY_MS } from "../constants.js";
 
 const LOG_PREFIX = "[HashtagPreferences]";
@@ -57,54 +61,6 @@ const DECRYPT_TIMEOUT_MS = 30000;
 // PERF: Reduced from 3s to 1.5s — extensions that already granted permission
 // should recover near-instantly. Shorter delay speeds up the login path.
 const DECRYPT_RETRY_DELAY_MS = NETWORK_RETRY_DELAY_MS;
-const MAX_DECRYPT_RETRY_DELAY_MS = 60000;
-
-// Transient decrypt failures that must RETRY in the background rather than give
-// up: our own timeout, a severed nip-07 message port ("message channel closed"),
-// and the circuit breaker's fast-fail. Without this a brief channel drop during
-// the login burst abandons hashtag prefs until a refresh (KNOWN_BUGS #0).
-const TRANSIENT_DECRYPT_ERROR_CODES = new Set([
-  "hashtag-preferences-decrypt-timeout",
-  "nip07-channel-unresponsive",
-]);
-const TRANSIENT_DECRYPT_MESSAGE_PATTERNS = [
-  "message channel closed",
-  "could not establish connection",
-  "receiving end does not exist",
-  "extension context invalidated",
-  "connection lost",
-  "channel is unresponsive",
-];
-function isTransientDecryptError(error) {
-  if (!error) return false;
-  if (error.code && TRANSIENT_DECRYPT_ERROR_CODES.has(error.code)) return true;
-  const message =
-    typeof error.message === "string" ? error.message.toLowerCase() : "";
-  if (TRANSIENT_DECRYPT_MESSAGE_PATTERNS.some((p) => message.includes(p))) {
-    return true;
-  }
-  // decryptEvent wraps the per-scheme Promise.any failures in a generic
-  // "decrypt-failed" error and nests the real causes under .errors/.cause —
-  // recurse so a channel-death sub-error still triggers a retry.
-  const nested = Array.isArray(error.errors)
-    ? error.errors
-    : Array.isArray(error.cause)
-      ? error.cause
-      : null;
-  if (nested) {
-    return nested.some((entry) => isTransientDecryptError(entry?.error || entry));
-  }
-  return false;
-}
-
-function computeRetryDelay(baseDelayMs, attempt) {
-  const normalizedAttempt =
-    Number.isFinite(attempt) && attempt > 0 ? Math.floor(attempt) : 0;
-  const multiplier = 2 ** normalizedAttempt;
-  const nextDelay = Math.max(250, Math.floor(baseDelayMs * multiplier));
-  return Math.min(MAX_DECRYPT_RETRY_DELAY_MS, nextDelay);
-}
-
 class TinyEventEmitter {
   constructor() {
     this.listeners = new Map();
@@ -153,23 +109,6 @@ const EVENTS = Object.freeze({
   CHANGE: "change",
 });
 
-function normalizeHexPubkey(pubkey) {
-  if (typeof pubkey !== "string") {
-    return null;
-  }
-
-  const trimmed = pubkey.trim();
-  if (!trimmed) {
-    return null;
-  }
-
-  if (HEX64_REGEX.test(trimmed)) {
-    return trimmed.toLowerCase();
-  }
-
-  return null;
-}
-
 function normalizeEncryptionToken(value) {
   if (typeof value !== "string") {
     return "";