diff --git a/CHANGES.md b/CHANGES.md
index 5de819ea1e4d..29711c60ce6c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,104 @@
+Synapse 1.21.0rc1 (2020-10-01)
+==============================
+
+Features
+--------
+
+- Require the user to confirm that their password should be reset after clicking the email confirmation link. ([\#8004](https://github.com/matrix-org/synapse/issues/8004))
+- Add an admin API `GET /_synapse/admin/v1/event_reports` to read entries of table `event_reports`. Contributed by @dklimpel. ([\#8217](https://github.com/matrix-org/synapse/issues/8217))
+- Consolidate the SSO error template across all configuration. ([\#8248](https://github.com/matrix-org/synapse/issues/8248), [\#8405](https://github.com/matrix-org/synapse/issues/8405))
+- Add a configuration option to specify a whitelist of domains that a user can be redirected to after validating their email or phone number. ([\#8275](https://github.com/matrix-org/synapse/issues/8275), [\#8417](https://github.com/matrix-org/synapse/issues/8417))
+- Add experimental support for sharding event persister. ([\#8294](https://github.com/matrix-org/synapse/issues/8294), [\#8387](https://github.com/matrix-org/synapse/issues/8387), [\#8396](https://github.com/matrix-org/synapse/issues/8396), [\#8419](https://github.com/matrix-org/synapse/issues/8419))
+- Add the room topic and avatar to the room details admin API. ([\#8305](https://github.com/matrix-org/synapse/issues/8305))
+- Add an admin API for querying rooms where a user is a member. Contributed by @dklimpel. ([\#8306](https://github.com/matrix-org/synapse/issues/8306))
+- Add `uk.half-shot.msc2778.login.application_service` login type to allow appservices to login. ([\#8320](https://github.com/matrix-org/synapse/issues/8320))
+- Add a configuration option that allows existing users to log in with OpenID Connect. Contributed by @BBBSnowball and @OmmyZhang. ([\#8345](https://github.com/matrix-org/synapse/issues/8345))
+- Add prometheus metrics for replication requests. ([\#8406](https://github.com/matrix-org/synapse/issues/8406))
+- Support passing additional single sign-on parameters to the client. ([\#8413](https://github.com/matrix-org/synapse/issues/8413))
+- Add experimental reporting of metrics on expensive rooms for state-resolution. ([\#8420](https://github.com/matrix-org/synapse/issues/8420))
+- Add experimental prometheus metric to track numbers of "large" rooms for state resolutiom. ([\#8425](https://github.com/matrix-org/synapse/issues/8425))
+- Add prometheus metrics to track federation delays. ([\#8430](https://github.com/matrix-org/synapse/issues/8430))
+
+
+Bugfixes
+--------
+
+- Fix a bug in the media repository where remote thumbnails with the same size but different crop methods would overwrite each other. Contributed by @deepbluev7. ([\#7124](https://github.com/matrix-org/synapse/issues/7124))
+- Fix inconsistent handling of non-existent push rules, and stop tracking the `enabled` state of removed push rules. ([\#7796](https://github.com/matrix-org/synapse/issues/7796))
+- Fix a longstanding bug when storing a media file with an empty `upload_name`. ([\#7905](https://github.com/matrix-org/synapse/issues/7905))
+- Fix messages not being sent over federation until an event is sent into the same room. ([\#8230](https://github.com/matrix-org/synapse/issues/8230), [\#8247](https://github.com/matrix-org/synapse/issues/8247), [\#8258](https://github.com/matrix-org/synapse/issues/8258), [\#8272](https://github.com/matrix-org/synapse/issues/8272), [\#8322](https://github.com/matrix-org/synapse/issues/8322))
+- Fix a longstanding bug where files that could not be thumbnailed would result in an Internal Server Error. ([\#8236](https://github.com/matrix-org/synapse/issues/8236), [\#8435](https://github.com/matrix-org/synapse/issues/8435))
+- Upgrade minimum version of `canonicaljson` to version 1.4.0, to fix an unicode encoding issue. ([\#8262](https://github.com/matrix-org/synapse/issues/8262))
+- Fix longstanding bug which could lead to incomplete database upgrades on SQLite. ([\#8265](https://github.com/matrix-org/synapse/issues/8265))
+- Fix stack overflow when stderr is redirected to the logging system, and the logging system encounters an error. ([\#8268](https://github.com/matrix-org/synapse/issues/8268))
+- Fix a bug which cause the logging system to report errors, if `DEBUG` was enabled and no `context` filter was applied. ([\#8278](https://github.com/matrix-org/synapse/issues/8278))
+- Fix edge case where push could get delayed for a user until a later event was pushed. ([\#8287](https://github.com/matrix-org/synapse/issues/8287))
+- Fix fetching malformed events from remote servers. ([\#8324](https://github.com/matrix-org/synapse/issues/8324))
+- Fix `UnboundLocalError` from occuring when appservices send a malformed register request. ([\#8329](https://github.com/matrix-org/synapse/issues/8329))
+- Don't send push notifications to expired user accounts. ([\#8353](https://github.com/matrix-org/synapse/issues/8353))
+- Fix a regression in v1.19.0 with reactivating users through the admin API. ([\#8362](https://github.com/matrix-org/synapse/issues/8362))
+- Fix a bug where during device registration the length of the device name wasn't limited. ([\#8364](https://github.com/matrix-org/synapse/issues/8364))
+- Include `guest_access` in the fields that are checked for null bytes when updating `room_stats_state`. Broke in v1.7.2. ([\#8373](https://github.com/matrix-org/synapse/issues/8373))
+- Fix theoretical race condition where events are not sent down `/sync` if the synchrotron worker is restarted without restarting other workers. ([\#8374](https://github.com/matrix-org/synapse/issues/8374))
+- Fix a bug which could cause errors in rooms with malformed membership events, on servers using sqlite. ([\#8385](https://github.com/matrix-org/synapse/issues/8385))
+- Fix "Re-starting finished log context" warning when receiving an event we already had over federation. ([\#8398](https://github.com/matrix-org/synapse/issues/8398))
+- Fix incorrect handling of timeouts on outgoing HTTP requests. ([\#8400](https://github.com/matrix-org/synapse/issues/8400))
+- Fix a regression in v1.20.0 in the `synapse_port_db` script regarding the `ui_auth_sessions_ips` table. ([\#8410](https://github.com/matrix-org/synapse/issues/8410))
+- Remove unnecessary 3PID registration check when resetting password via an email address. Bug introduced in v0.34.0rc2. ([\#8414](https://github.com/matrix-org/synapse/issues/8414))
+
+
+Improved Documentation
+----------------------
+
+- Add `/_synapse/client` to the reverse proxy documentation. ([\#8227](https://github.com/matrix-org/synapse/issues/8227))
+- Add note to the reverse proxy settings documentation about disabling Apache's mod_security2. Contributed by Julian Fietkau (@jfietkau). ([\#8375](https://github.com/matrix-org/synapse/issues/8375))
+- Improve description of `server_name` config option in `homserver.yaml`. ([\#8415](https://github.com/matrix-org/synapse/issues/8415))
+
+
+Deprecations and Removals
+-------------------------
+
+- Drop support for `prometheus_client` older than 0.4.0. ([\#8426](https://github.com/matrix-org/synapse/issues/8426))
+
+
+Internal Changes
+----------------
+
+- Fix tests on distros which disable TLSv1.0. Contributed by @danc86. ([\#8208](https://github.com/matrix-org/synapse/issues/8208))
+- Simplify the distributor code to avoid unnecessary work. ([\#8216](https://github.com/matrix-org/synapse/issues/8216))
+- Remove the `populate_stats_process_rooms_2` background job and restore functionality to `populate_stats_process_rooms`. ([\#8243](https://github.com/matrix-org/synapse/issues/8243))
+- Clean up type hints for `PaginationConfig`. ([\#8250](https://github.com/matrix-org/synapse/issues/8250), [\#8282](https://github.com/matrix-org/synapse/issues/8282))
+- Track the latest event for every destination and room for catch-up after federation outage. ([\#8256](https://github.com/matrix-org/synapse/issues/8256))
+- Fix non-user visible bug in implementation of `MultiWriterIdGenerator.get_current_token_for_writer`. ([\#8257](https://github.com/matrix-org/synapse/issues/8257))
+- Switch to the JSON implementation from the standard library. ([\#8259](https://github.com/matrix-org/synapse/issues/8259))
+- Add type hints to `synapse.util.async_helpers`. ([\#8260](https://github.com/matrix-org/synapse/issues/8260))
+- Simplify tests that mock asynchronous functions. ([\#8261](https://github.com/matrix-org/synapse/issues/8261))
+- Add type hints to `StreamToken` and `RoomStreamToken` classes. ([\#8279](https://github.com/matrix-org/synapse/issues/8279))
+- Change `StreamToken.room_key` to be a `RoomStreamToken` instance. ([\#8281](https://github.com/matrix-org/synapse/issues/8281))
+- Refactor notifier code to correctly use the max event stream position. ([\#8288](https://github.com/matrix-org/synapse/issues/8288))
+- Use slotted classes where possible. ([\#8296](https://github.com/matrix-org/synapse/issues/8296))
+- Support testing the local Synapse checkout against the [Complement homeserver test suite](https://github.com/matrix-org/complement/). ([\#8317](https://github.com/matrix-org/synapse/issues/8317))
+- Update outdated usages of `metaclass` to python 3 syntax. ([\#8326](https://github.com/matrix-org/synapse/issues/8326))
+- Move lint-related dependencies to package-extra field, update CONTRIBUTING.md to utilise this. ([\#8330](https://github.com/matrix-org/synapse/issues/8330), [\#8377](https://github.com/matrix-org/synapse/issues/8377))
+- Use the `admin_patterns` helper in additional locations. ([\#8331](https://github.com/matrix-org/synapse/issues/8331))
+- Fix test logging to allow braces in log output. ([\#8335](https://github.com/matrix-org/synapse/issues/8335))
+- Remove `__future__` imports related to Python 2 compatibility. ([\#8337](https://github.com/matrix-org/synapse/issues/8337))
+- Simplify `super()` calls to Python 3 syntax. ([\#8344](https://github.com/matrix-org/synapse/issues/8344))
+- Fix bad merge from `release-v1.20.0` branch to `develop`. ([\#8354](https://github.com/matrix-org/synapse/issues/8354))
+- Factor out a `_send_dummy_event_for_room` method. ([\#8370](https://github.com/matrix-org/synapse/issues/8370))
+- Improve logging of state resolution. ([\#8371](https://github.com/matrix-org/synapse/issues/8371))
+- Add type annotations to `SimpleHttpClient`. ([\#8372](https://github.com/matrix-org/synapse/issues/8372))
+- Refactor ID generators to use `async with` syntax. ([\#8383](https://github.com/matrix-org/synapse/issues/8383))
+- Add `EventStreamPosition` type. ([\#8388](https://github.com/matrix-org/synapse/issues/8388))
+- Create a mechanism for marking tests "logcontext clean". ([\#8399](https://github.com/matrix-org/synapse/issues/8399))
+- A pair of tiny cleanups in the federation request code. ([\#8401](https://github.com/matrix-org/synapse/issues/8401))
+- Add checks on startup that PostgreSQL sequences are consistent with their associated tables. ([\#8402](https://github.com/matrix-org/synapse/issues/8402))
+- Do not include appservice users when calculating the total MAU for a server. ([\#8404](https://github.com/matrix-org/synapse/issues/8404))
+- Typing fixes for `synapse.handlers.federation`. ([\#8422](https://github.com/matrix-org/synapse/issues/8422))
+- Various refactors to simplify stream token handling. ([\#8423](https://github.com/matrix-org/synapse/issues/8423))
+- Make stream token serializing/deserializing async. ([\#8427](https://github.com/matrix-org/synapse/issues/8427))
+
+
 Synapse 1.20.1 (2020-09-24)
 ===========================
 
diff --git a/changelog.d/7124.bugfix b/changelog.d/7124.bugfix
deleted file mode 100644
index 8fd177780d7d..000000000000
--- a/changelog.d/7124.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug in the media repository where remote thumbnails with the same size but different crop methods would overwrite each other. Contributed by @deepbluev7.
diff --git a/changelog.d/7796.bugfix b/changelog.d/7796.bugfix
deleted file mode 100644
index 65e5eb42a248..000000000000
--- a/changelog.d/7796.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix inconsistent handling of non-existent push rules, and stop tracking the `enabled` state of removed push rules.
diff --git a/changelog.d/7905.bugfix b/changelog.d/7905.bugfix
deleted file mode 100644
index e60e62441210..000000000000
--- a/changelog.d/7905.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a longstanding bug when storing a media file with an empty `upload_name`.
diff --git a/changelog.d/8004.feature b/changelog.d/8004.feature
deleted file mode 100644
index a91b75e0e0fd..000000000000
--- a/changelog.d/8004.feature
+++ /dev/null
@@ -1 +0,0 @@
-Require the user to confirm that their password should be reset after clicking the email confirmation link.
\ No newline at end of file
diff --git a/changelog.d/8208.misc b/changelog.d/8208.misc
deleted file mode 100644
index e65da88c4643..000000000000
--- a/changelog.d/8208.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fix tests on distros which disable TLSv1.0. Contributed by @danc86.
diff --git a/changelog.d/8216.misc b/changelog.d/8216.misc
deleted file mode 100644
index b38911b0e582..000000000000
--- a/changelog.d/8216.misc
+++ /dev/null
@@ -1 +0,0 @@
-Simplify the distributor code to avoid unnecessary work.
diff --git a/changelog.d/8217.feature b/changelog.d/8217.feature
deleted file mode 100644
index 899cbf14ef56..000000000000
--- a/changelog.d/8217.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add an admin API `GET /_synapse/admin/v1/event_reports` to read entries of table `event_reports`. Contributed by @dklimpel.
\ No newline at end of file
diff --git a/changelog.d/8227.doc b/changelog.d/8227.doc
deleted file mode 100644
index 4a43015a8306..000000000000
--- a/changelog.d/8227.doc
+++ /dev/null
@@ -1 +0,0 @@
-Add `/_synapse/client` to the reverse proxy documentation.
diff --git a/changelog.d/8230.bugfix b/changelog.d/8230.bugfix
deleted file mode 100644
index 532d0e22fefb..000000000000
--- a/changelog.d/8230.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix messages over federation being lost until an event is sent into the same room.
diff --git a/changelog.d/8236.bugfix b/changelog.d/8236.bugfix
deleted file mode 100644
index 6f048710159f..000000000000
--- a/changelog.d/8236.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a longstanding bug where files that could not be thumbnailed would result in an Internal Server Error.
diff --git a/changelog.d/8243.misc b/changelog.d/8243.misc
deleted file mode 100644
index f7375d32d33e..000000000000
--- a/changelog.d/8243.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove the 'populate_stats_process_rooms_2' background job and restore functionality to 'populate_stats_process_rooms'.
\ No newline at end of file
diff --git a/changelog.d/8247.bugfix b/changelog.d/8247.bugfix
deleted file mode 100644
index 532d0e22fefb..000000000000
--- a/changelog.d/8247.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix messages over federation being lost until an event is sent into the same room.
diff --git a/changelog.d/8248.feature b/changelog.d/8248.feature
deleted file mode 100644
index f3c4a74bc79b..000000000000
--- a/changelog.d/8248.feature
+++ /dev/null
@@ -1 +0,0 @@
-Consolidate the SSO error template across all configuration.
diff --git a/changelog.d/8250.misc b/changelog.d/8250.misc
deleted file mode 100644
index b6896a9300d5..000000000000
--- a/changelog.d/8250.misc
+++ /dev/null
@@ -1 +0,0 @@
-Clean up type hints for `PaginationConfig`.
diff --git a/changelog.d/8256.misc b/changelog.d/8256.misc
deleted file mode 100644
index bf0ba767307d..000000000000
--- a/changelog.d/8256.misc
+++ /dev/null
@@ -1 +0,0 @@
-Track the latest event for every destination and room for catch-up after federation outage.
diff --git a/changelog.d/8257.misc b/changelog.d/8257.misc
deleted file mode 100644
index 47ac583eb4f2..000000000000
--- a/changelog.d/8257.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fix non-user visible bug in implementation of `MultiWriterIdGenerator.get_current_token_for_writer`.
diff --git a/changelog.d/8258.bugfix b/changelog.d/8258.bugfix
deleted file mode 100644
index 532d0e22fefb..000000000000
--- a/changelog.d/8258.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix messages over federation being lost until an event is sent into the same room.
diff --git a/changelog.d/8259.misc b/changelog.d/8259.misc
deleted file mode 100644
index a26779a664c7..000000000000
--- a/changelog.d/8259.misc
+++ /dev/null
@@ -1 +0,0 @@
-Switch to the JSON implementation from the standard library.
diff --git a/changelog.d/8260.misc b/changelog.d/8260.misc
deleted file mode 100644
index 164eea8b59eb..000000000000
--- a/changelog.d/8260.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add type hints to `synapse.util.async_helpers`.
diff --git a/changelog.d/8261.misc b/changelog.d/8261.misc
deleted file mode 100644
index bc91e9375ce0..000000000000
--- a/changelog.d/8261.misc
+++ /dev/null
@@ -1 +0,0 @@
-Simplify tests that mock asynchronous functions.
diff --git a/changelog.d/8262.bugfix b/changelog.d/8262.bugfix
deleted file mode 100644
index 2b84927de3ee..000000000000
--- a/changelog.d/8262.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Upgrade canonicaljson to version 1.4.0 to fix an unicode encoding issue.
diff --git a/changelog.d/8265.bugfix b/changelog.d/8265.bugfix
deleted file mode 100644
index 981a836d218c..000000000000
--- a/changelog.d/8265.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix logstanding bug which could lead to incomplete database upgrades on SQLite.
diff --git a/changelog.d/8268.bugfix b/changelog.d/8268.bugfix
deleted file mode 100644
index 4b15a60253b7..000000000000
--- a/changelog.d/8268.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix stack overflow when stderr is redirected to the logging system, and the logging system encounters an error.
diff --git a/changelog.d/8272.bugfix b/changelog.d/8272.bugfix
deleted file mode 100644
index 532d0e22fefb..000000000000
--- a/changelog.d/8272.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix messages over federation being lost until an event is sent into the same room.
diff --git a/changelog.d/8275.feature b/changelog.d/8275.feature
deleted file mode 100644
index 17549c3df39a..000000000000
--- a/changelog.d/8275.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add a config option to specify a whitelist of domains that a user can be redirected to after validating their email or phone number.
\ No newline at end of file
diff --git a/changelog.d/8278.bugfix b/changelog.d/8278.bugfix
deleted file mode 100644
index 50e40ca2a9da..000000000000
--- a/changelog.d/8278.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug which cause the logging system to report errors, if `DEBUG` was enabled and no `context` filter was applied.
diff --git a/changelog.d/8279.misc b/changelog.d/8279.misc
deleted file mode 100644
index 99f669001f18..000000000000
--- a/changelog.d/8279.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add type hints to `StreamToken` and `RoomStreamToken` classes.
diff --git a/changelog.d/8281.misc b/changelog.d/8281.misc
deleted file mode 100644
index 74357120a726..000000000000
--- a/changelog.d/8281.misc
+++ /dev/null
@@ -1 +0,0 @@
-Change `StreamToken.room_key` to be a `RoomStreamToken` instance.
diff --git a/changelog.d/8282.misc b/changelog.d/8282.misc
deleted file mode 100644
index b6896a9300d5..000000000000
--- a/changelog.d/8282.misc
+++ /dev/null
@@ -1 +0,0 @@
-Clean up type hints for `PaginationConfig`.
diff --git a/changelog.d/8287.bugfix b/changelog.d/8287.bugfix
deleted file mode 100644
index 839781aa0753..000000000000
--- a/changelog.d/8287.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix edge case where push could get delayed for a user until a later event was pushed.
diff --git a/changelog.d/8288.misc b/changelog.d/8288.misc
deleted file mode 100644
index c08a53a5ee27..000000000000
--- a/changelog.d/8288.misc
+++ /dev/null
@@ -1 +0,0 @@
-Refactor notifier code to correctly use the max event stream position.
diff --git a/changelog.d/8294.feature b/changelog.d/8294.feature
deleted file mode 100644
index b363e929ea8c..000000000000
--- a/changelog.d/8294.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add experimental support for sharding event persister.
diff --git a/changelog.d/8296.misc b/changelog.d/8296.misc
deleted file mode 100644
index f593a5b34778..000000000000
--- a/changelog.d/8296.misc
+++ /dev/null
@@ -1 +0,0 @@
-Use slotted classes where possible.
diff --git a/changelog.d/8305.feature b/changelog.d/8305.feature
deleted file mode 100644
index 862dfdf95986..000000000000
--- a/changelog.d/8305.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add the room topic and avatar to the room details admin API.
diff --git a/changelog.d/8306.feature b/changelog.d/8306.feature
deleted file mode 100644
index 5c23da4030ff..000000000000
--- a/changelog.d/8306.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add an admin API for querying rooms where a user is a member. Contributed by @dklimpel.
\ No newline at end of file
diff --git a/changelog.d/8317.feature b/changelog.d/8317.feature
deleted file mode 100644
index f9edda099c40..000000000000
--- a/changelog.d/8317.feature
+++ /dev/null
@@ -1 +0,0 @@
-Support testing the local Synapse checkout against the [Complement homeserver test suite](https://github.com/matrix-org/complement/).
\ No newline at end of file
diff --git a/changelog.d/8320.feature b/changelog.d/8320.feature
deleted file mode 100644
index 475a5fe62d97..000000000000
--- a/changelog.d/8320.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add `uk.half-shot.msc2778.login.application_service` login type to allow appservices to login.
diff --git a/changelog.d/8322.bugfix b/changelog.d/8322.bugfix
deleted file mode 100644
index 532d0e22fefb..000000000000
--- a/changelog.d/8322.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix messages over federation being lost until an event is sent into the same room.
diff --git a/changelog.d/8324.bugfix b/changelog.d/8324.bugfix
deleted file mode 100644
index 32788a92848c..000000000000
--- a/changelog.d/8324.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix fetching events from remote servers that are malformed.
diff --git a/changelog.d/8326.misc b/changelog.d/8326.misc
deleted file mode 100644
index 985d2c027aa9..000000000000
--- a/changelog.d/8326.misc
+++ /dev/null
@@ -1 +0,0 @@
-Update outdated usages of `metaclass` to python 3 syntax.
\ No newline at end of file
diff --git a/changelog.d/8329.bugfix b/changelog.d/8329.bugfix
deleted file mode 100644
index 2f71f1f4b956..000000000000
--- a/changelog.d/8329.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix UnboundLocalError from occuring when appservices send malformed register request.
\ No newline at end of file
diff --git a/changelog.d/8330.misc b/changelog.d/8330.misc
deleted file mode 100644
index fbfdd524730a..000000000000
--- a/changelog.d/8330.misc
+++ /dev/null
@@ -1 +0,0 @@
-Move lint-related dependencies to package-extra field, update CONTRIBUTING.md to utilise this.
diff --git a/changelog.d/8331.misc b/changelog.d/8331.misc
deleted file mode 100644
index 0e1bae20efa3..000000000000
--- a/changelog.d/8331.misc
+++ /dev/null
@@ -1 +0,0 @@
-Use the `admin_patterns` helper in additional locations.
diff --git a/changelog.d/8335.misc b/changelog.d/8335.misc
deleted file mode 100644
index 7e0a4c7d839f..000000000000
--- a/changelog.d/8335.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fix test logging to allow braces in log output.
\ No newline at end of file
diff --git a/changelog.d/8337.misc b/changelog.d/8337.misc
deleted file mode 100644
index 4daf27220443..000000000000
--- a/changelog.d/8337.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove `__future__` imports related to Python 2 compatibility.
\ No newline at end of file
diff --git a/changelog.d/8344.misc b/changelog.d/8344.misc
deleted file mode 100644
index 0b342d513727..000000000000
--- a/changelog.d/8344.misc
+++ /dev/null
@@ -1 +0,0 @@
-Simplify `super()` calls to Python 3 syntax.
diff --git a/changelog.d/8345.feature b/changelog.d/8345.feature
deleted file mode 100644
index 4ee5b6a56e37..000000000000
--- a/changelog.d/8345.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add a configuration option that allows existing users to log in with OpenID Connect. Contributed by @BBBSnowball and @OmmyZhang.
diff --git a/changelog.d/8353.bugfix b/changelog.d/8353.bugfix
deleted file mode 100644
index 45fc0adb8dd5..000000000000
--- a/changelog.d/8353.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Don't send push notifications to expired user accounts.
diff --git a/changelog.d/8354.misc b/changelog.d/8354.misc
deleted file mode 100644
index 1d33cde2da6c..000000000000
--- a/changelog.d/8354.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fix bad merge from `release-v1.20.0` branch to `develop`.
diff --git a/changelog.d/8362.bugfix b/changelog.d/8362.bugfix
deleted file mode 100644
index 4e50067c87b5..000000000000
--- a/changelog.d/8362.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fixed a regression in v1.19.0 with reactivating users through the admin API.
diff --git a/changelog.d/8364.bugfix b/changelog.d/8364.bugfix
deleted file mode 100644
index 7b82cbc3881c..000000000000
--- a/changelog.d/8364.bugfix
+++ /dev/null
@@ -1,2 +0,0 @@
-Fix a bug where during device registration the length of the device name wasn't
-limited.
diff --git a/changelog.d/8370.misc b/changelog.d/8370.misc
deleted file mode 100644
index 1aaac1e0bf90..000000000000
--- a/changelog.d/8370.misc
+++ /dev/null
@@ -1 +0,0 @@
-Factor out a `_send_dummy_event_for_room` method.
diff --git a/changelog.d/8371.misc b/changelog.d/8371.misc
deleted file mode 100644
index 6a54a9496afb..000000000000
--- a/changelog.d/8371.misc
+++ /dev/null
@@ -1 +0,0 @@
-Improve logging of state resolution.
diff --git a/changelog.d/8372.misc b/changelog.d/8372.misc
deleted file mode 100644
index a56e36de4be1..000000000000
--- a/changelog.d/8372.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add type annotations to `SimpleHttpClient`.
diff --git a/changelog.d/8373.bugfix b/changelog.d/8373.bugfix
deleted file mode 100644
index e9d66a2088c4..000000000000
--- a/changelog.d/8373.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Include `guest_access` in the fields that are checked for null bytes when updating `room_stats_state`. Broke in v1.7.2.
\ No newline at end of file
diff --git a/changelog.d/8374.bugfix b/changelog.d/8374.bugfix
deleted file mode 100644
index 155bc3404f52..000000000000
--- a/changelog.d/8374.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix theoretical race condition where events are not sent down `/sync` if the synchrotron worker is restarted without restarting other workers.
diff --git a/changelog.d/8375.doc b/changelog.d/8375.doc
deleted file mode 100644
index d291fb92fa18..000000000000
--- a/changelog.d/8375.doc
+++ /dev/null
@@ -1 +0,0 @@
-Add note to the reverse proxy settings documentation about disabling Apache's mod_security2. Contributed by Julian Fietkau (@jfietkau).
diff --git a/changelog.d/8377.misc b/changelog.d/8377.misc
deleted file mode 100644
index fbfdd524730a..000000000000
--- a/changelog.d/8377.misc
+++ /dev/null
@@ -1 +0,0 @@
-Move lint-related dependencies to package-extra field, update CONTRIBUTING.md to utilise this.
diff --git a/changelog.d/8383.misc b/changelog.d/8383.misc
deleted file mode 100644
index cb8318bf5704..000000000000
--- a/changelog.d/8383.misc
+++ /dev/null
@@ -1 +0,0 @@
-Refactor ID generators to use `async with` syntax.
diff --git a/changelog.d/8385.bugfix b/changelog.d/8385.bugfix
deleted file mode 100644
index c42502a8e020..000000000000
--- a/changelog.d/8385.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug which could cause errors in rooms with malformed membership events, on servers using sqlite.
diff --git a/changelog.d/8386.bugfix b/changelog.d/8386.bugfix
deleted file mode 100644
index 24983a1e950f..000000000000
--- a/changelog.d/8386.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a bug introduced in v1.20.0 which caused the `synapse_port_db` script to fail.
diff --git a/changelog.d/8387.feature b/changelog.d/8387.feature
deleted file mode 100644
index b363e929ea8c..000000000000
--- a/changelog.d/8387.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add experimental support for sharding event persister.
diff --git a/changelog.d/8388.misc b/changelog.d/8388.misc
deleted file mode 100644
index aaaef88b661e..000000000000
--- a/changelog.d/8388.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add `EventStreamPosition` type.
diff --git a/changelog.d/8396.feature b/changelog.d/8396.feature
deleted file mode 100644
index b363e929ea8c..000000000000
--- a/changelog.d/8396.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add experimental support for sharding event persister.
diff --git a/changelog.d/8398.bugfix b/changelog.d/8398.bugfix
deleted file mode 100644
index e432aeebf190..000000000000
--- a/changelog.d/8398.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix "Re-starting finished log context" warning when receiving an event we already had over federation.
diff --git a/changelog.d/8399.misc b/changelog.d/8399.misc
deleted file mode 100644
index ce6e8123cf8b..000000000000
--- a/changelog.d/8399.misc
+++ /dev/null
@@ -1 +0,0 @@
-Create a mechanism for marking tests "logcontext clean".
diff --git a/changelog.d/8400.bugfix b/changelog.d/8400.bugfix
deleted file mode 100644
index 835658ba5eac..000000000000
--- a/changelog.d/8400.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix incorrect handling of timeouts on outgoing HTTP requests.
diff --git a/changelog.d/8401.misc b/changelog.d/8401.misc
deleted file mode 100644
index 27fd7ab129d9..000000000000
--- a/changelog.d/8401.misc
+++ /dev/null
@@ -1 +0,0 @@
-A pair of tiny cleanups in the federation request code.
diff --git a/changelog.d/8402.misc b/changelog.d/8402.misc
deleted file mode 100644
index ad1804d207aa..000000000000
--- a/changelog.d/8402.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add checks on startup that PostgreSQL sequences are consistent with their associated tables.
diff --git a/changelog.d/8404.misc b/changelog.d/8404.misc
deleted file mode 100644
index 7aadded6c1dd..000000000000
--- a/changelog.d/8404.misc
+++ /dev/null
@@ -1 +0,0 @@
-Do not include appservice users when calculating the total MAU for a server.
diff --git a/changelog.d/8405.feature b/changelog.d/8405.feature
deleted file mode 100644
index f3c4a74bc79b..000000000000
--- a/changelog.d/8405.feature
+++ /dev/null
@@ -1 +0,0 @@
-Consolidate the SSO error template across all configuration.
diff --git a/changelog.d/8406.feature b/changelog.d/8406.feature
deleted file mode 100644
index 1c6472ae7eae..000000000000
--- a/changelog.d/8406.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add prometheus metrics for replication requests.
diff --git a/changelog.d/8410.bugfix b/changelog.d/8410.bugfix
deleted file mode 100644
index 1323ddc525db..000000000000
--- a/changelog.d/8410.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Fix a v1.20.0 regression in the `synapse_port_db` script regarding the `ui_auth_sessions_ips` table.
diff --git a/changelog.d/8413.feature b/changelog.d/8413.feature
deleted file mode 100644
index abe40a901cf6..000000000000
--- a/changelog.d/8413.feature
+++ /dev/null
@@ -1 +0,0 @@
-Support passing additional single sign-on parameters to the client.
diff --git a/changelog.d/8414.bugfix b/changelog.d/8414.bugfix
deleted file mode 100644
index 315876e89238..000000000000
--- a/changelog.d/8414.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Remove unnecessary 3PID registration check when resetting password via an email address. Bug introduced in v0.34.0rc2.
\ No newline at end of file
diff --git a/changelog.d/8415.doc b/changelog.d/8415.doc
deleted file mode 100644
index 28b579853364..000000000000
--- a/changelog.d/8415.doc
+++ /dev/null
@@ -1 +0,0 @@
-Improve description of `server_name` config option in `homserver.yaml`.
\ No newline at end of file
diff --git a/changelog.d/8417.feature b/changelog.d/8417.feature
deleted file mode 100644
index 17549c3df39a..000000000000
--- a/changelog.d/8417.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add a config option to specify a whitelist of domains that a user can be redirected to after validating their email or phone number.
\ No newline at end of file
diff --git a/changelog.d/8419.feature b/changelog.d/8419.feature
deleted file mode 100644
index b363e929ea8c..000000000000
--- a/changelog.d/8419.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add experimental support for sharding event persister.
diff --git a/changelog.d/8420.feature b/changelog.d/8420.feature
deleted file mode 100644
index 9d6849624d48..000000000000
--- a/changelog.d/8420.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add experimental reporting of metrics on expensive rooms for state-resolution.
diff --git a/changelog.d/8422.misc b/changelog.d/8422.misc
deleted file mode 100644
index 03fba120c6d9..000000000000
--- a/changelog.d/8422.misc
+++ /dev/null
@@ -1 +0,0 @@
-Typing fixes for `synapse.handlers.federation`.
diff --git a/changelog.d/8423.misc b/changelog.d/8423.misc
deleted file mode 100644
index 7260e3fa4182..000000000000
--- a/changelog.d/8423.misc
+++ /dev/null
@@ -1 +0,0 @@
-Various refactors to simplify stream token handling.
diff --git a/changelog.d/8425.feature b/changelog.d/8425.feature
deleted file mode 100644
index b4ee5bb74b9d..000000000000
--- a/changelog.d/8425.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add experimental prometheus metric to track numbers of "large" rooms for state resolutiom.
diff --git a/changelog.d/8426.removal b/changelog.d/8426.removal
deleted file mode 100644
index a56277fe7ad6..000000000000
--- a/changelog.d/8426.removal
+++ /dev/null
@@ -1 +0,0 @@
-Drop support for `prometheus_client` older than 0.4.0.
diff --git a/changelog.d/8427.misc b/changelog.d/8427.misc
deleted file mode 100644
index c9656b9112b2..000000000000
--- a/changelog.d/8427.misc
+++ /dev/null
@@ -1 +0,0 @@
-Make stream token serializing/deserializing async.
diff --git a/changelog.d/8430.feature b/changelog.d/8430.feature
deleted file mode 100644
index 1f31d42bc1de..000000000000
--- a/changelog.d/8430.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add prometheus metrics to track federation delays.
diff --git a/synapse/__init__.py b/synapse/__init__.py
index e40b582bd585..47069745080f 100644
--- a/synapse/__init__.py
+++ b/synapse/__init__.py
@@ -48,7 +48,7 @@
 except ImportError:
     pass
 
-__version__ = "1.20.1"
+__version__ = "1.21.0rc1"
 
 if bool(os.environ.get("SYNAPSE_TEST_PATCH_LOG_CONTEXTS", False)):
     # We import here so that we don't have to install a bunch of deps when
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index ae6822d6e742..e1192b47cdb0 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -637,7 +637,7 @@ async def _generate_thumbnails(
             thumbnailer = Thumbnailer(input_path)
         except ThumbnailError as e:
             logger.warning(
-                "Unable to generate thumbnails for remote media %s from %s using a method of %s and type of %s: %s",
+                "Unable to generate thumbnails for remote media %s from %s of type %s: %s",
                 media_id,
                 server_name,
                 media_type,