[Full Changelog](https://github.com/matrix-org/matrix-js-sdk/compare/v6.0.0...v6.1.0-rc.1) * Remove support for asymmetric 4S encryption [\#1373](https://github.com/matrix-org/matrix-js-sdk/pull/1373) * Increase timeout for 2nd phase of Olm session creation [\#1367](https://github.com/matrix-org/matrix-js-sdk/pull/1367) * Add logging on decryption retries [\#1366](https://github.com/matrix-org/matrix-js-sdk/pull/1366) * Emit event when a trusted self-key is stored [\#1364](https://github.com/matrix-org/matrix-js-sdk/pull/1364) * Customize error payload for oversized messages [\#1352](https://github.com/matrix-org/matrix-js-sdk/pull/1352) * Return null for key backup state when we haven't checked yet [\#1363](https://github.com/matrix-org/matrix-js-sdk/pull/1363) * Added a progressCallback for backup key loading [\#1351](https://github.com/matrix-org/matrix-js-sdk/pull/1351) * Add initialFetch param to willUpdateDevices / devicesUpdated [\#1360](https://github.com/matrix-org/matrix-js-sdk/pull/1360) * Fix race between sending .request and receiving .ready over to_device [\#1359](https://github.com/matrix-org/matrix-js-sdk/pull/1359) * Handle race between sending and await next event from other party [\#1357](https://github.com/matrix-org/matrix-js-sdk/pull/1357) * Add crypto.willUpdateDevices event and make getStoredDevices/getStoredDevicesForUser synchronous [\#1354](https://github.com/matrix-org/matrix-js-sdk/pull/1354) * Fix sender of local echo events in unsigned redactions [\#1350](https://github.com/matrix-org/matrix-js-sdk/pull/1350) * Remove redundant key backup setup path [\#1353](https://github.com/matrix-org/matrix-js-sdk/pull/1353) * Remove some dead code from _retryDecryption [\#1349](https://github.com/matrix-org/matrix-js-sdk/pull/1349) * Don't send key requests until after sync processing is finished [\#1348](https://github.com/matrix-org/matrix-js-sdk/pull/1348) * Prevent attempts to send olm messages to ourselves [\#1346](https://github.com/matrix-org/matrix-js-sdk/pull/1346) * Retry account data upload requests [\#1345](https://github.com/matrix-org/matrix-js-sdk/pull/1345) * Log first known index with megolm session updates [\#1344](https://github.com/matrix-org/matrix-js-sdk/pull/1344) * Prune to_device messages to avoid sending empty messages [\#1343](https://github.com/matrix-org/matrix-js-sdk/pull/1343) * Convert bunch of things to TypeScript [\#1335](https://github.com/matrix-org/matrix-js-sdk/pull/1335) * Add logging when making new Olm sessions [\#1342](https://github.com/matrix-org/matrix-js-sdk/pull/1342) * Fix: handle filter not found [\#1340](https://github.com/matrix-org/matrix-js-sdk/pull/1340) * Make getAccountDataFromServer return null if not found [\#1338](https://github.com/matrix-org/matrix-js-sdk/pull/1338) * Fix setDefaultKeyId to fail if the request fails [\#1336](https://github.com/matrix-org/matrix-js-sdk/pull/1336) * Document setRoomEncryption not modifying room state [\#1328](https://github.com/matrix-org/matrix-js-sdk/pull/1328) * Fix: don't do extra /filter request when enabling lazy loading of members [\#1332](https://github.com/matrix-org/matrix-js-sdk/pull/1332) * Reject attemptAuth promise if no auth flow found [\#1329](https://github.com/matrix-org/matrix-js-sdk/pull/1329) * Fix FilterComponent allowed_values check [\#1327](https://github.com/matrix-org/matrix-js-sdk/pull/1327) * Serialise Olm prekey decryptions [\#1326](https://github.com/matrix-org/matrix-js-sdk/pull/1326) * Fix: crash when backup key needs fixing from corruption issue [\#1324](https://github.com/matrix-org/matrix-js-sdk/pull/1324) * Fix cross-signing/SSSS reset [\#1322](https://github.com/matrix-org/matrix-js-sdk/pull/1322) * Implement QR code reciprocate for self-verification with untrusted MSK [\#1320](https://github.com/matrix-org/matrix-js-sdk/pull/1320)