diff --git a/version.py b/version.py
index 50366b1ddf..7f31ba9d0c 100644
--- a/version.py
+++ b/version.py
@@ -48,4 +48,4 @@ API_FEATURE_LEVEL = 175
 #   historical commits sharing the same major version, in which case a
 #   minor version bump suffices.
 
-PROVISION_VERSION = (233, 2)
+PROVISION_VERSION = (233, 3)
diff --git a/zerver/migrations/0441_backfill_realmfilter_url_template.py b/zerver/migrations/0441_backfill_realmfilter_url_template.py
new file mode 100644
index 0000000000..c173a1f8a5
--- /dev/null
+++ b/zerver/migrations/0441_backfill_realmfilter_url_template.py
@@ -0,0 +1,48 @@
+# Generated by Django 4.0.7 on 2022-10-02 20:50
+
+import re
+
+import uri_template
+from django.db import migrations
+from django.db.backends.base.schema import BaseDatabaseSchemaEditor
+from django.db.migrations.state import StateApps
+
+
+def transform_to_url_template_syntax(
+    apps: StateApps, schema_editor: BaseDatabaseSchemaEditor
+) -> None:
+    linkifier_model = apps.get_model("zerver", "RealmFilter")
+
+    linkifiers = linkifier_model.objects.all()
+    # Matches anything of the form %(variable_name)s
+    var_pattern = re.compile(r"(?<!%)((?:%%)*)%\(([a-zA-Z0-9_-]+)\)s")
+    escape_table = str.maketrans(
+        {
+            "{": "%7B",
+            "}": "%7D",
+        }
+    )
+    for linkifier in linkifiers:
+        converted_template = linkifier.url_format_string.translate(escape_table)
+        # Replace format string variables with the RFC 6570 URI Template syntax
+        converted_template = var_pattern.sub(r"\1{\2}", converted_template).replace("%%", "%")
+        if not uri_template.validate(converted_template):
+            raise RuntimeError(
+                f'Failed to convert url format "{var_pattern}". The converted template "{converted_template}" is invalid.'
+            )
+        linkifier.url_template = converted_template
+    linkifier_model.objects.bulk_update(linkifiers, fields=["url_template"])
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("zerver", "0440_realmfilter_url_template"),
+    ]
+
+    operations = [
+        migrations.RunPython(
+            transform_to_url_template_syntax,
+            reverse_code=migrations.RunPython.noop,
+            elidable=True,
+        ),
+    ]
diff --git a/zerver/tests/test_migrations.py b/zerver/tests/test_migrations.py
index 52555aa1da..bab4c46fe0 100644
--- a/zerver/tests/test_migrations.py
+++ b/zerver/tests/test_migrations.py
@@ -4,16 +4,11 @@
 # You can also read
 #   https://www.caktusgroup.com/blog/2016/02/02/writing-unit-tests-django-migrations/
 # to get a tutorial on the framework that inspired this feature.
-from typing import Optional
-from unittest import skip
 
-import orjson
 from django.db.migrations.state import StateApps
-from django.utils.timezone import now as timezone_now
 
 from zerver.lib.test_classes import MigrationsTestCase
 from zerver.lib.test_helpers import use_db_models
-from zerver.models import get_stream
 
 # Important note: These tests are very expensive, and details of
 # Django's database transaction model mean it does not super work to
@@ -31,390 +26,88 @@ from zerver.models import get_stream
 # been tested for a migration being merged.
 
 
-@skip("Fails because newer migrations have since been merged.")  # nocoverage # skipped
-class MessageEditHistoryLegacyFormats(MigrationsTestCase):
-    migrate_from = "0376_set_realmemoji_author_and_reupload_realmemoji"
-    migrate_to = "0377_message_edit_history_format"
-
-    msg_id: Optional[int] = None
+class LinkifierURLFormatString(MigrationsTestCase):
+    migrate_from = "0440_realmfilter_url_template"
+    migrate_to = "0441_backfill_realmfilter_url_template"
 
     @use_db_models
     def setUpBeforeMigration(self, apps: StateApps) -> None:
-        Recipient = apps.get_model("zerver", "Recipient")
-        Message = apps.get_model("zerver", "Message")
+        RealmFilter = apps.get_model("zerver", "RealmFilter")
 
         iago = self.example_user("iago")
-        stream_name = "Denmark"
-        denmark = get_stream(stream_name, iago.realm)
-        denmark_recipient = Recipient.objects.get(type=2, type_id=denmark.id)
 
-        self.msg_id = Message.objects.create(
-            recipient_id=denmark_recipient.id,
-            subject="topic 4",
-            sender_id=iago.id,
-            sending_client_id=1,
-            content="current message text",
-            date_sent=timezone_now(),
-        ).id
+        urls = [
+            "http://example.com/",
+            "https://example.com/",
+            "https://user:password@example.com/",
+            "https://example.com/@user/thing",
+            "https://example.com/!path",
+            "https://example.com/foo.bar",
+            "https://example.com/foo[bar]",
+            "https://example.com/{foo}",
+            "https://example.com/{foo}{bars}",
+            "https://example.com/{foo}/and/{bar}",
+            "https://example.com/?foo={foo}",
+            "https://example.com/%ab",
+            "https://example.com/%ba",
+            "https://example.com/%21",
+            "https://example.com/words%20with%20spaces",
+            "https://example.com/back%20to%20{back}",
+            "https://example.com/encoded%2fwith%2fletters",
+            "https://example.com/encoded%2Fwith%2Fupper%2Fcase%2Fletters",
+            "https://example.com/%%",
+            "https://example.com/%%(",
+            "https://example.com/%%()",
+            "https://example.com/%%(foo",
+            "https://example.com/%%(foo)",
+            "https://example.com/%%(foo)s",
+            "https://example.com/%(foo)s",
+            "https://example.com/%(foo)s%(bar)s",
+        ]
+        self.linkifier_ids = []
 
-        # topic edits contain only "prev_subject" field.
-        # stream edits contain only "prev_stream" field.
-        msg = Message.objects.filter(id=self.msg_id).first()
-        msg.edit_history = orjson.dumps(
-            [
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405050,
-                    "prev_stream": 3,
-                    "prev_subject": "topic 3",
-                },
-                {"user_id": 11, "timestamp": 1644405040, "prev_stream": 2},
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405030,
-                    "prev_content": "test content and topic edit",
-                    "prev_rendered_content": "<p>test content and topic edit</p>",
-                    "prev_rendered_content_version": 1,
-                    "prev_subject": "topic 2",
-                },
-                {"user_id": 11, "timestamp": 1644405020, "prev_subject": "topic 1"},
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405010,
-                    "prev_content": "test content only edit",
-                    "prev_rendered_content": "<p>test content only edit</p>",
-                    "prev_rendered_content_version": 1,
-                },
-            ]
-        ).decode()
-        msg.save(update_fields=["edit_history"])
+        for index, url in enumerate(urls):
+            self.linkifier_ids.append(
+                RealmFilter.objects.create(
+                    realm=iago.realm,
+                    pattern=f"dummy{index}",
+                    url_format_string=url,
+                ).id
+            )
 
-    def test_message_legacy_edit_history_format(self) -> None:
-        Message = self.apps.get_model("zerver", "Message")
-        Recipient = self.apps.get_model("zerver", "Recipient")
+    def test_converted_url_templates(self) -> None:
+        RealmFilter = self.apps.get_model("zerver", "RealmFilter")
 
-        iago = self.example_user("iago")
-        stream_name = "Denmark"
-        denmark = get_stream(stream_name, iago.realm)
+        expected_urls = [
+            "http://example.com/",
+            "https://example.com/",
+            "https://user:password@example.com/",
+            "https://example.com/@user/thing",
+            "https://example.com/!path",
+            "https://example.com/foo.bar",
+            "https://example.com/foo[bar]",
+            "https://example.com/%7Bfoo%7D",
+            "https://example.com/%7Bfoo%7D%7Bbars%7D",
+            "https://example.com/%7Bfoo%7D/and/%7Bbar%7D",
+            "https://example.com/?foo=%7Bfoo%7D",
+            "https://example.com/%ab",
+            "https://example.com/%ba",
+            "https://example.com/%21",
+            "https://example.com/words%20with%20spaces",
+            "https://example.com/back%20to%20%7Bback%7D",
+            "https://example.com/encoded%2fwith%2fletters",
+            "https://example.com/encoded%2Fwith%2Fupper%2Fcase%2Fletters",
+            "https://example.com/%",
+            "https://example.com/%(",
+            "https://example.com/%()",
+            "https://example.com/%(foo",
+            "https://example.com/%(foo)",
+            "https://example.com/%(foo)s",
+            "https://example.com/{foo}",
+            "https://example.com/{foo}{bar}",
+        ]
 
-        msg = Message.objects.filter(id=self.msg_id).first()
-        msg_stream_id = Recipient.objects.get(id=msg.recipient_id).type_id
-        new_edit_history = orjson.loads(msg.edit_history)
-
-        self.assert_length(new_edit_history, 5)
-
-        # stream and topic edit entry
-        self.assertFalse("prev_subject" in new_edit_history[0])
-        self.assertEqual(new_edit_history[0]["prev_topic"], "topic 3")
-        self.assertEqual(new_edit_history[0]["topic"], msg.subject)
-        self.assertEqual(new_edit_history[0]["prev_stream"], 3)
-        self.assertEqual(new_edit_history[0]["stream"], msg_stream_id)
-        self.assertEqual(new_edit_history[0]["stream"], denmark.id)
-        self.assertEqual(
-            set(new_edit_history[0].keys()),
-            {"timestamp", "prev_topic", "topic", "prev_stream", "stream", "user_id"},
-        )
-
-        # stream only edit entry
-        self.assertEqual(new_edit_history[1]["prev_stream"], 2)
-        self.assertEqual(new_edit_history[1]["stream"], 3)
-        self.assertEqual(
-            set(new_edit_history[1].keys()), {"timestamp", "prev_stream", "stream", "user_id"}
-        )
-
-        # topic and content edit entry
-        self.assertFalse("prev_subject" in new_edit_history[2])
-        self.assertEqual(new_edit_history[2]["prev_topic"], "topic 2")
-        self.assertEqual(new_edit_history[2]["topic"], "topic 3")
-        self.assertEqual(new_edit_history[2]["prev_content"], "test content and topic edit")
-        self.assertEqual(
-            new_edit_history[2]["prev_rendered_content"], "<p>test content and topic edit</p>"
-        )
-        self.assertEqual(new_edit_history[2]["prev_rendered_content_version"], 1)
-        self.assertEqual(
-            set(new_edit_history[2].keys()),
-            {
-                "timestamp",
-                "prev_topic",
-                "topic",
-                "prev_content",
-                "prev_rendered_content",
-                "prev_rendered_content_version",
-                "user_id",
-            },
-        )
-
-        # topic only edit entry
-        self.assertFalse("prev_subject" in new_edit_history[3])
-        self.assertEqual(new_edit_history[3]["prev_topic"], "topic 1")
-        self.assertEqual(new_edit_history[3]["topic"], "topic 2")
-        self.assertEqual(
-            set(new_edit_history[3].keys()), {"timestamp", "prev_topic", "topic", "user_id"}
-        )
-
-        # content only edit entry - not retested because never changes
-        self.assertEqual(new_edit_history[4]["prev_content"], "test content only edit")
-        self.assertEqual(
-            new_edit_history[4]["prev_rendered_content"], "<p>test content only edit</p>"
-        )
-        self.assertEqual(new_edit_history[4]["prev_rendered_content_version"], 1)
-        self.assertEqual(
-            set(new_edit_history[4].keys()),
-            {
-                "timestamp",
-                "prev_content",
-                "prev_rendered_content",
-                "prev_rendered_content_version",
-                "user_id",
-            },
-        )
-
-
-@skip("Fails because newer migrations have since been merged.")  # nocoverage # skipped
-class MessageEditHistoryModernFormats(MigrationsTestCase):
-    migrate_from = "0376_set_realmemoji_author_and_reupload_realmemoji"
-    migrate_to = "0377_message_edit_history_format"
-
-    msg_id: Optional[int] = None
-
-    @use_db_models
-    def setUpBeforeMigration(self, apps: StateApps) -> None:
-        Recipient = apps.get_model("zerver", "Recipient")
-        Message = apps.get_model("zerver", "Message")
-
-        iago = self.example_user("iago")
-        stream_name = "Denmark"
-        denmark = get_stream(stream_name, iago.realm)
-        denmark_recipient = Recipient.objects.get(type=2, type_id=denmark.id)
-
-        self.msg_id = Message.objects.create(
-            recipient_id=denmark_recipient.id,
-            subject="topic 4",
-            sender_id=iago.id,
-            sending_client_id=1,
-            content="current message text",
-            date_sent=timezone_now(),
-        ).id
-
-        msg = Message.objects.filter(id=self.msg_id).first()
-        msg_stream_id = Recipient.objects.get(id=msg.recipient_id).type_id
-
-        # topic edits contain "topic" and "prev_topic" fields.
-        # stream edits contain "stream" and "prev_stream" fields.
-        msg.edit_history = orjson.dumps(
-            [
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405050,
-                    "stream": msg_stream_id,
-                    "prev_stream": 3,
-                    "topic": msg.subject,
-                    "prev_topic": "topic 3",
-                },
-                {"user_id": 11, "timestamp": 1644405040, "prev_stream": 2, "stream": 3},
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405030,
-                    "prev_content": "test content and topic edit",
-                    "prev_rendered_content": "<p>test content and topic edit</p>",
-                    "prev_rendered_content_version": 1,
-                    "prev_topic": "topic 2",
-                    "topic": "topic 3",
-                },
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405020,
-                    "prev_topic": "topic 1",
-                    "topic": "topic 2",
-                },
-            ]
-        ).decode()
-        msg.save(update_fields=["edit_history"])
-
-    def test_message_modern_edit_history_format(self) -> None:
-        Message = self.apps.get_model("zerver", "Message")
-        Recipient = self.apps.get_model("zerver", "Recipient")
-
-        iago = self.example_user("iago")
-        stream_name = "Denmark"
-        denmark = get_stream(stream_name, iago.realm)
-
-        msg = Message.objects.filter(id=self.msg_id).first()
-        msg_stream_id = Recipient.objects.get(id=msg.recipient_id).type_id
-        new_edit_history = orjson.loads(msg.edit_history)
-
-        self.assert_length(new_edit_history, 4)
-
-        # stream and topic edit entry
-        self.assertEqual(new_edit_history[0]["prev_topic"], "topic 3")
-        self.assertEqual(new_edit_history[0]["topic"], msg.subject)
-        self.assertEqual(new_edit_history[0]["prev_stream"], 3)
-        self.assertEqual(new_edit_history[0]["stream"], msg_stream_id)
-        self.assertEqual(new_edit_history[0]["stream"], denmark.id)
-        self.assertEqual(
-            set(new_edit_history[0].keys()),
-            {"timestamp", "prev_topic", "topic", "prev_stream", "stream", "user_id"},
-        )
-
-        # stream only edit entry
-        self.assertEqual(new_edit_history[1]["prev_stream"], 2)
-        self.assertEqual(new_edit_history[1]["stream"], 3)
-        self.assertEqual(
-            set(new_edit_history[1].keys()), {"timestamp", "prev_stream", "stream", "user_id"}
-        )
-
-        # topic and content edit entry
-        self.assertEqual(new_edit_history[2]["prev_topic"], "topic 2")
-        self.assertEqual(new_edit_history[2]["topic"], "topic 3")
-        self.assertEqual(new_edit_history[2]["prev_content"], "test content and topic edit")
-        self.assertEqual(
-            new_edit_history[2]["prev_rendered_content"], "<p>test content and topic edit</p>"
-        )
-        self.assertEqual(new_edit_history[2]["prev_rendered_content_version"], 1)
-        self.assertEqual(
-            set(new_edit_history[2].keys()),
-            {
-                "timestamp",
-                "prev_topic",
-                "topic",
-                "prev_content",
-                "prev_rendered_content",
-                "prev_rendered_content_version",
-                "user_id",
-            },
-        )
-
-        # topic only edit entry
-        self.assertEqual(new_edit_history[3]["prev_topic"], "topic 1")
-        self.assertEqual(new_edit_history[3]["topic"], "topic 2")
-        self.assertEqual(
-            set(new_edit_history[3].keys()), {"timestamp", "prev_topic", "topic", "user_id"}
-        )
-
-
-@skip("Fails because newer migrations have since been merged.")  # nocoverage # skipped
-class MessageEditHistoryIntermediateFormats(MigrationsTestCase):
-    migrate_from = "0376_set_realmemoji_author_and_reupload_realmemoji"
-    migrate_to = "0377_message_edit_history_format"
-
-    msg_id: Optional[int] = None
-
-    @use_db_models
-    def setUpBeforeMigration(self, apps: StateApps) -> None:
-        Recipient = apps.get_model("zerver", "Recipient")
-        Message = apps.get_model("zerver", "Message")
-
-        iago = self.example_user("iago")
-        stream_name = "Denmark"
-        denmark = get_stream(stream_name, iago.realm)
-        denmark_recipient = Recipient.objects.get(type=2, type_id=denmark.id)
-
-        self.msg_id = Message.objects.create(
-            recipient_id=denmark_recipient.id,
-            subject="topic 4",
-            sender_id=iago.id,
-            sending_client_id=1,
-            content="current message text",
-            date_sent=timezone_now(),
-        ).id
-
-        msg = Message.objects.filter(id=self.msg_id).first()
-        msg_stream_id = Recipient.objects.get(id=msg.recipient_id).type_id
-
-        # topic edits contain "prev_subject", "topic" and "prev_topic" fields.
-        # stream edits contain "stream" and "prev_stream" fields.
-        msg.edit_history = orjson.dumps(
-            [
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405050,
-                    "stream": msg_stream_id,
-                    "prev_stream": 3,
-                    "topic": msg.subject,
-                    "prev_topic": "topic 3",
-                    "prev_subject": "topic 3",
-                },
-                {"user_id": 11, "timestamp": 1644405040, "prev_stream": 2, "stream": 3},
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405030,
-                    "prev_content": "test content and topic edit",
-                    "prev_rendered_content": "<p>test content and topic edit</p>",
-                    "prev_rendered_content_version": 1,
-                    "prev_topic": "topic 2",
-                    "prev_subject": "topic 2",
-                    "topic": "topic 3",
-                },
-                {
-                    "user_id": 11,
-                    "timestamp": 1644405020,
-                    "prev_topic": "topic 1",
-                    "prev_subject": "topic 1",
-                    "topic": "topic 2",
-                },
-            ]
-        ).decode()
-        msg.save(update_fields=["edit_history"])
-
-    def test_message_temporary_edit_history_format(self) -> None:
-        Message = self.apps.get_model("zerver", "Message")
-        Recipient = self.apps.get_model("zerver", "Recipient")
-
-        iago = self.example_user("iago")
-        stream_name = "Denmark"
-        denmark = get_stream(stream_name, iago.realm)
-
-        msg = Message.objects.filter(id=self.msg_id).first()
-        msg_stream_id = Recipient.objects.get(id=msg.recipient_id).type_id
-        new_edit_history = orjson.loads(msg.edit_history)
-
-        self.assert_length(new_edit_history, 4)
-
-        # stream and topic edit entry
-        self.assertFalse("prev_subject" in new_edit_history[0])
-        self.assertEqual(new_edit_history[0]["prev_topic"], "topic 3")
-        self.assertEqual(new_edit_history[0]["topic"], msg.subject)
-        self.assertEqual(new_edit_history[0]["prev_stream"], 3)
-        self.assertEqual(new_edit_history[0]["stream"], msg_stream_id)
-        self.assertEqual(new_edit_history[0]["stream"], denmark.id)
-        self.assertEqual(
-            set(new_edit_history[0].keys()),
-            {"timestamp", "prev_topic", "topic", "prev_stream", "stream", "user_id"},
-        )
-
-        # stream only edit entry
-        self.assertEqual(new_edit_history[1]["prev_stream"], 2)
-        self.assertEqual(new_edit_history[1]["stream"], 3)
-        self.assertEqual(
-            set(new_edit_history[1].keys()), {"timestamp", "prev_stream", "stream", "user_id"}
-        )
-
-        # topic and content edit entry
-        self.assertFalse("prev_subject" in new_edit_history[2])
-        self.assertEqual(new_edit_history[2]["prev_topic"], "topic 2")
-        self.assertEqual(new_edit_history[2]["topic"], "topic 3")
-        self.assertEqual(new_edit_history[2]["prev_content"], "test content and topic edit")
-        self.assertEqual(
-            new_edit_history[2]["prev_rendered_content"], "<p>test content and topic edit</p>"
-        )
-        self.assertEqual(new_edit_history[2]["prev_rendered_content_version"], 1)
-        self.assertEqual(
-            set(new_edit_history[2].keys()),
-            {
-                "timestamp",
-                "prev_topic",
-                "topic",
-                "prev_content",
-                "prev_rendered_content",
-                "prev_rendered_content_version",
-                "user_id",
-            },
-        )
-
-        # topic only edit entry
-        self.assertFalse("prev_subject" in new_edit_history[3])
-        self.assertEqual(new_edit_history[3]["prev_topic"], "topic 1")
-        self.assertEqual(new_edit_history[3]["topic"], "topic 2")
-        self.assertEqual(
-            set(new_edit_history[3].keys()), {"timestamp", "prev_topic", "topic", "user_id"}
-        )
+        for linkifier_id, expected in zip(self.linkifier_ids, expected_urls):
+            linkifier = RealmFilter.objects.filter(id=linkifier_id).first()
+            self.assertIsNotNone(linkifier)
+            self.assertEqual(linkifier.url_template, expected)