Yrs

New Observer API (#385): all subscription types now are described as a single yrs::Subscription type. observe methods no longer require mut ref to shared collection or document.
Hook and BranchID logical pointers (#393): collection refs such as ArrayRef, TextRef, MapRef now expose root and hook methods, that can be used to get a logical reference to a given type. This reference can later on be used to try to obtain an actual ref (it could also possibly return None if reference was already garbage collected).
Removed Doc::get_or_insert_xml_element and Doc::get_or_insert_xml_text - these types are not meant to be used as root level types and doing so may cause data loss due to limitations on how root-level types are represented in lib0 encoding.
Replaced rand crate with fastrand(#394): smaller binary size and better support for Web Assembly.
Moved Awareness and y-sync protocol into yrs::sync module (#395).
Changes in the internal representation of Doc updates (#365) - this should result in better performance and less memory used.

Ywasm

Rewritten the library. Shared types are now using logical pointer in order to avoid possible segfaults in WASM VM.
Removed Doc.getXmlText and Doc.getXmlElement- these types are not meant to be used as root level types and doing so may cause data loss due to limitations on how root-level types are represented in lib0 encoding. Use Doc.getXmlFragment instead and insert XML nodes into it.
YXmlText and YXmlElements can now be used as prelim types.
Removed xmlElement.insertXmlText/xmlElement.insertXmlElement: now there's a single xmlElement.insert method that can accept prelim versions of YXmlText and YXmlElement.
Logical pointers can now be accessed via ref.id property of shared collection types. They can be materialised back into refs via YTransaction.get method.

Removed yxmlelem and yxmltext functions - these types are not meant to be used as root level types and doing so may cause data loss due to limitations on how root-level types are represented in lib0 encoding. Use yxmlfragment instead and insert XML nodes into it.
Replaced ytransaction_alive with ybranch_alive.
Exposed logical collection pointers via YBranchId - now Branch* can mapped back and forth to YBranchId through ybranch_id and ybranch_get functions. In case when Branch* has already been garbage collected and is no longer valid, ybranch_get will return NULL.