Added support for building with the new React Native architecture enabled on Android. Thanks to Nikolai Samorodov / @zabutok for contributing the fix. (#5032)
Exposed SyncError.logUrl which contains the URL to the server log related to the sync error. (#5609)
Added a new error class CompensatingWriteError which indicates that one or more object changes have been reverted by the server. This can happen when the client creates/updates objects that do not match any subscription, or performs writes on an object it didn't have permission to access. (#5599)
Performance improvement for the following queries (realm/realm-core#6376):
- Significant (~75%) improvement when counting (Realm.Results#length) the number of exact matches (with no other query conditions) on a string/int/uuid/objectId property that has an index. This improvement will be especially noticeable if there are a large number of results returned (duplicate values).
- Significant (~99%) improvement when querying for an exact match on a date property that has an index.
- Significant (~99%) improvement when querying for a case insensitive match on a mixed property that has an index.
- Moderate (~25%) improvement when querying for an exact match on a bool property that has an index.
- Small (~5%) improvement when querying for a case insensitive match on a mixed property that does not have an index.
Added a THROW_ON_GLOBAL_REALM which will enable throwing when the app is accessing the Realm without first importing it from the Realm package.

Fixed

Fixed bootstrapping the native module on Android. Seen as Exception in HostObject::get for prop 'Realm': java.lang.NoClassDefFoundError: io.realm.react.RealmReactModule. (#5666, since v12.0.0-alpha.0)
Fixed passing RealmObject instances between shared Realms. (#5634, since v12.0.0-alpha.0)
Fixed a crash when querying a mixed property with a string operator (contains/like/beginswith/endswith) or with case insensitivity. ([realm/realm-core#6376](https://github.com/realm/realm-core/issues/6376, since v10.5.0)
Querying for equality of a string on an indexed mixed property was returning case insensitive matches. For example querying for myIndexedMixed == "Foo" would incorrectly match on values of "foo" or "FOO". (realm/realm-core#6376, since v10.5.0)
Adding an index to a mixed property on a non-empty class/objectType would crash with an assertion. (realm/realm-core#6376, since v10.5.0)
Realm.App.Sync#pause() could hold a reference to the database open after shutting down the sync session, preventing users from being able to delete the Realm. (realm/realm-core#6372, since v11.5.0)
Fixed a bug that may have resulted in Realm.Results and Realm.List being in different orders on different devices. Moreover, some cases of the error message Invalid prior_size may have be fixed too. (realm/realm-core#6191, since v10.15.0)
Exposed Sync as named export. #5649
Fixed the return value of App.allUsers to return a record with the User.id as the key and the User as the value. #5671

Compatibility

React Native >= v0.71.0
Realm Studio v13.0.0.
File format: generates Realms with format v23 (reads and upgrades file format v5 or later for non-synced Realm, upgrades file format v10 or later for synced Realms).