diff --git a/assets/reader.css b/assets/reader.css
index 435e8ff..33f6624 100644
--- a/assets/reader.css
+++ b/assets/reader.css
@@ -993,6 +993,40 @@
   color: var(--color-primary);
 }
 
+/* Override upstream .mention { display: grid } for bio content */
+.ap-profile__bio .h-card {
+  display: inline;
+}
+
+.ap-profile__bio .h-card a,
+.ap-profile__bio a.u-url.mention {
+  display: inline;
+  white-space: nowrap;
+}
+
+.ap-profile__bio .h-card a span,
+.ap-profile__bio a.u-url.mention span {
+  display: inline;
+}
+
+.ap-profile__bio a.mention.hashtag {
+  display: inline;
+  white-space: nowrap;
+}
+
+.ap-profile__bio a.mention.hashtag span {
+  display: inline;
+}
+
+/* Mastodon invisible/ellipsis spans for long URLs in bios */
+.ap-profile__bio .invisible {
+  display: none;
+}
+
+.ap-profile__bio .ellipsis::after {
+  content: "…";
+}
+
 .ap-profile__actions {
   display: flex;
   flex-wrap: wrap;
diff --git a/package.json b/package.json
index c553e25..ac0718e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@rmdes/indiekit-endpoint-activitypub",
-  "version": "2.0.9",
+  "version": "2.0.10",
   "description": "ActivityPub federation endpoint for Indiekit via Fedify. Adds full fediverse support: actor, inbox, outbox, followers, following, syndication, and Mastodon migration.",
   "keywords": [
     "indiekit",
diff --git a/views/activitypub-public-profile.njk b/views/activitypub-public-profile.njk
index 4e6e7bd..88263a9 100644
--- a/views/activitypub-public-profile.njk
+++ b/views/activitypub-public-profile.njk
@@ -177,6 +177,17 @@
     .ap-pub__bio p { margin: 0 0 var(--space-s); }
     .ap-pub__bio p:last-child { margin-bottom: 0; }
 
+    /* Mastodon mention/hashtag formatting */
+    .ap-pub__bio .h-card { display: inline; }
+    .ap-pub__bio .h-card a,
+    .ap-pub__bio a.u-url.mention { display: inline; white-space: nowrap; }
+    .ap-pub__bio .h-card a span,
+    .ap-pub__bio a.u-url.mention span { display: inline; }
+    .ap-pub__bio a.mention.hashtag { display: inline; white-space: nowrap; }
+    .ap-pub__bio a.mention.hashtag span { display: inline; }
+    .ap-pub__bio .invisible { display: none; }
+    .ap-pub__bio .ellipsis::after { content: "…"; }
+
     /* ================================================================
        Profile fields
        ================================================================ */