SteamOS 3.7.7 Beta brings a Battery Charge Limit option and improved Lenovo Legion Go S support

Valve have released SteamOS 3.7.7 Beta “Sunny & Gizmo” with the noted changes including the new Battery Charge Limit option along with more work for the Lenovo Legion Go S.
A bit confusing this one, since Valve say in this SteamOS Beta how it includes the Battery Charge Limit option, which was actually rolled out earlier in May via a Steam Deck Beta Client update. Presumably then, this is work directly in SteamOS to support it for more devices.
Valve are also working right up against the clock here for the Legion Go S, since the SteamOS version is due to launch really soon. From the changelog:
General
- Added Battery Charge Limit control to Settings -> Power.
- This option allows you to set a maximum charge limit for your Steam Deck.
- Limiting the charge limit to 80% can be beneficial for long term battery health. This can be useful if your Steam Deck is constantly being charged (e.g. docked), or very rarely has its battery depleted.
- Fixed a case where the performance overlay could spuriously appear and could not be disabled.
- Fixed an issue where exiting a game from the overlay could result in the UI getting stuck until a button is pressed.
- Desktop mode will no longer erroneously nag the user to install power profiles daemon.
- Added support for updating controller and system firmware on the Legion Go S.
This update is available via the Beta and Preview channels in Settings > System > System Update Channel.