The newest update on the League of Legends Client rework focuses on Chromium Embedded Framework. The last time this was updated was in November 2019, with version 74.
The top priority right now is updating the client's version of Chromium Embedded Framework (CEF)—the web browser at the heart of the League Client's architecture. The last time CEF was updated was November 2019; at the time of writing, the latest current version is CEF 91. Updating CEF to version 91 will reap a host of benefits, from reduced crashes to increased compatibility to better responsiveness and more. It is the single most impactful individual change we can make to improve the client.
Testing the new version of CEF internally is taking place, and already improvements in memory usage, and CPU utilization for the front end can be seen. A host of other benefits that will ultimately provide a better player experience when we launch is expected as well, but the developers also don't want to create risk by rushing things. There is a big opportunity to do right for all players, and the devs want to make sure the upgraded client is stable before being released live.
Other updates include:
Revisiting End Of Game (EOG). Developers are still in the process of identifying what improvements can be made to End Of Game (EOG), which is an area they will jump back into once CEF has been upgraded. EOG is frequently reported as a client pain point so they are going to continue the investigation and prioritize this work for the remainder of this year, and will work with other teams to see what improvements they can make.
Client stability during long sessions. One of the emergent focuses at the end of last year was addressing memory leaks, which cause the client to take up increasingly more memory as players play multiple games or leave their client idling for long stretches of time. (Good news here is that the CEF upgrade will help stability.) Digging deeper into client bug reports, developers noticed many players only experience issues if they have left their client open and/or resume using the client after coming out of PC sleep. They are working on a feature that will automatically close the client while in-game, if it takes up too much memory, to provide a refreshed client experience when the client relaunches into the post-game screen.