diff --git a/app/soapbox/__fixtures__/mastodon-instance-rc.json b/app/soapbox/__fixtures__/mastodon-instance-rc.json
new file mode 100644
index 000000000..277839d14
--- /dev/null
+++ b/app/soapbox/__fixtures__/mastodon-instance-rc.json
@@ -0,0 +1,123 @@
+{
+  "uri": "mastodon.social",
+  "title": "Mastodon",
+  "short_description": "Server run by the main developers of the project <img draggable=\"false\" alt=\"🐘\" class=\"emojione\" src=\"https://mastodon.social/emoji/1f418.svg\" /> It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!",
+  "description": "Server run by the main developers of the project <img draggable=\"false\" alt=\"🐘\" class=\"emojione\" src=\"https://mastodon.social/emoji/1f418.svg\" /> It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!",
+  "email": "staff@mastodon.social",
+  "version": "3.5.0rc1",
+  "urls": {
+    "streaming_api": "wss://mastodon.social"
+  },
+  "stats": {
+    "user_count": 635078,
+    "status_count": 34700866,
+    "domain_count": 21989
+  },
+  "thumbnail": "https://files.mastodon.social/site_uploads/files/000/000/001/original/vlcsnap-2018-08-27-16h43m11s127.png",
+  "languages": [
+    "en"
+  ],
+  "registrations": true,
+  "approval_required": false,
+  "invites_enabled": true,
+  "configuration": {
+    "statuses": {
+      "max_characters": 500,
+      "max_media_attachments": 4,
+      "characters_reserved_per_url": 23
+    },
+    "media_attachments": {
+      "supported_mime_types": [
+        "image/jpeg",
+        "image/png",
+        "image/gif",
+        "video/webm",
+        "video/mp4",
+        "video/quicktime",
+        "video/ogg",
+        "audio/wave",
+        "audio/wav",
+        "audio/x-wav",
+        "audio/x-pn-wave",
+        "audio/ogg",
+        "audio/vorbis",
+        "audio/mpeg",
+        "audio/mp3",
+        "audio/webm",
+        "audio/flac",
+        "audio/aac",
+        "audio/m4a",
+        "audio/x-m4a",
+        "audio/mp4",
+        "audio/3gpp",
+        "video/x-ms-asf"
+      ],
+      "image_size_limit": 10485760,
+      "image_matrix_limit": 16777216,
+      "video_size_limit": 41943040,
+      "video_frame_rate_limit": 60,
+      "video_matrix_limit": 2304000
+    },
+    "polls": {
+      "max_options": 4,
+      "max_characters_per_option": 50,
+      "min_expiration": 300,
+      "max_expiration": 2629746
+    }
+  },
+  "contact_account": {
+    "id": "1",
+    "username": "Gargron",
+    "acct": "Gargron",
+    "display_name": "Eugen",
+    "locked": false,
+    "bot": false,
+    "discoverable": true,
+    "group": false,
+    "created_at": "2016-03-16T00:00:00.000Z",
+    "note": "<p>Founder, CEO and lead developer <span class=\"h-card\"><a href=\"https://mastodon.social/@Mastodon\" class=\"u-url mention\">@<span>Mastodon</span></a></span>, Germany.</p>",
+    "url": "https://mastodon.social/@Gargron",
+    "avatar": "https://files.mastodon.social/accounts/avatars/000/000/001/original/ccb05a778962e171.png",
+    "avatar_static": "https://files.mastodon.social/accounts/avatars/000/000/001/original/ccb05a778962e171.png",
+    "header": "https://files.mastodon.social/accounts/headers/000/000/001/original/3b91c9965d00888b.jpeg",
+    "header_static": "https://files.mastodon.social/accounts/headers/000/000/001/original/3b91c9965d00888b.jpeg",
+    "followers_count": 99760,
+    "following_count": 274,
+    "statuses_count": 71657,
+    "last_status_at": "2022-03-17",
+    "emojis": [],
+    "fields": [
+      {
+        "name": "Patreon",
+        "value": "<a href=\"https://www.patreon.com/mastodon\" rel=\"me nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://www.</span><span class=\"\">patreon.com/mastodon</span><span class=\"invisible\"></span></a>",
+        "verified_at": null
+      }
+    ]
+  },
+  "rules": [
+    {
+      "id": "1",
+      "text": "Sexually explicit or violent media must be marked as sensitive when posting"
+    },
+    {
+      "id": "2",
+      "text": "No racism, sexism, homophobia, transphobia, xenophobia, or casteism"
+    },
+    {
+      "id": "3",
+      "text": "No incitement of violence or promotion of violent ideologies"
+    },
+    {
+      "id": "4",
+      "text": "No harassment, dogpiling or doxxing of other users"
+    },
+    {
+      "id": "5",
+      "text": "No content illegal in Germany"
+    },
+    {
+      "id": "7",
+      "text": "Do not share intentionally false or misleading information"
+    }
+  ]
+}
diff --git a/app/soapbox/normalizers/__tests__/instance-test.js b/app/soapbox/normalizers/__tests__/instance-test.js
index 2df36734f..f5fd4f6af 100644
--- a/app/soapbox/normalizers/__tests__/instance-test.js
+++ b/app/soapbox/normalizers/__tests__/instance-test.js
@@ -177,4 +177,11 @@ describe('normalizeInstance()', () => {
     expect(result.get('configuration') instanceof ImmutableMap).toBe(true);
     expect(result.get('description_limit')).toBe(1500);
   });
+
+  it('normalizes a Mastodon RC version', () => {
+    const instance = require('soapbox/__fixtures__/mastodon-instance-rc.json');
+    const result = normalizeInstance(instance);
+
+    expect(result.version).toEqual('3.5.0-rc1');
+  });
 });
diff --git a/app/soapbox/normalizers/instance.ts b/app/soapbox/normalizers/instance.ts
index 6e2c0b4f9..a33601bf9 100644
--- a/app/soapbox/normalizers/instance.ts
+++ b/app/soapbox/normalizers/instance.ts
@@ -84,6 +84,18 @@ const pleromaToMastodonConfig = (instance: ImmutableMap<string, any>) => {
 // Get the software's default attachment limit
 const getAttachmentLimit = (software: string) => software === PLEROMA ? Infinity : 4;
 
+// Normalize version
+const normalizeVersion = (instance: ImmutableMap<string, any>) => {
+  return instance.update('version', '0.0.0', version => {
+    // Handle Mastodon release candidates
+    if (new RegExp(/[0-9\.]+rc[0-9]+/g).test(version)) {
+      return version.split('rc').join('-rc');
+    } else {
+      return version;
+    }
+  });
+};
+
 // Normalize instance (Pleroma, Mastodon, etc.) to Mastodon's format
 export const normalizeInstance = (instance: Record<string, any>) => {
   return InstanceRecord(
@@ -101,6 +113,9 @@ export const normalizeInstance = (instance: Record<string, any>) => {
         return isNumber(value) ? value : getAttachmentLimit(software);
       });
 
+      // Normalize version
+      normalizeVersion(instance);
+
       // Merge defaults
       instance.mergeDeepWith(mergeDefined, InstanceRecord());
     }),