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@@ -431,6 +431,20 @@ The items below are planned improvements roughly ordered by user value. They are
 
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+### 9. Auto-Derive Display Casing from Mastodon Posts
+
+**Problem:** `displayTag` is currently set once at research/creation time from whatever the user typed. In reality Mastodon users have an established "canonical" capitalisation for a tag (e.g. `#StPatricksDay` rather than `#stpatricksday`) and our display tag should reflect that.
+
+**Plan:**
+- During each price update job the worker already fetches up to 200 posts. The Mastodon API returns each post's `tags` array where `name` contains the tag as typed by the poster (e.g. `StPatricksDay`).
+- Count the frequency of each distinct casing variant seen across all fetched posts for the hashtag being updated.
+- If the most frequent variant differs from the current `displayTag`, update `Hashtag.displayTag` as part of the price update transaction.
+- Only update when a variant accounts for a meaningful majority (e.g. ≥ 50% of occurrences) to avoid flip-flopping on low-signal posts.
+- Implementation touches: `mastodon.ts` already returns `post.tags` from `getPostsData()` — add a `casing` field to the result (`{ postsPerHour, relatedTags, displayTag? }`); worker checks the returned `displayTag` and includes it in the Prisma update when it differs.
+- No schema changes required — `displayTag` already exists on `Hashtag`.
+
+---
+
 ### Other Ideas / Nice-to-Haves
 
 - **Hedge funds**: group of players pool money into a shared portfolio, one designated fund manager places trades.