Webapp v12.3.0

This release adds an experimental Buckets channel type, which provides S3-backed group storage organized by folders, limited by Roles, and readable and writable by Tlonbot. It also adds Notebook activity indicators and folder and note counts, more detailed reaction notifications on web, and a cleaner note context menu, along with fixes for mention nicknames, disappearing code blocks when editing, incorrect Notebook navigation, DM invitations requiring a refresh, and various background errors.

Hash: 0vv.takv8.ufv6f.pm991.op9ve.3o239.rm1tm.1cnpq.47br1.goiou.8qgk7

• Adds an experimental channel type, Buckets. Buckets are S3-backed storage channels for your group; able to be organized by folders and viewer-access-limited by Roles. Tlonbot can read from and write to Buckets channels. You can preview the feature by visiting Settings → Experimental Features and switching on "Enable Buckets channels."
• Adds an indicator of Notebook channel activity in the top-level Group listing.
• Adds a folder and note count to Notebook channels.
• Adds more detail to web notifications when someone reacts to your message.
• Improves the layout of the context menu for individual notes in Notebook channels.
• Fixes an issue where @-mentioning someone you just DM'd with would unreliably display their set nickname.
• Fixes an issue where nicknames containing emoji would show a black underline under the @-mention highlight in the chat input.
• Fixes an issue where editing a message containing a code block would cause the code block to disappear.
• Fixes an issue where navigating to a group would unreliably (and incorrectly) navigate deep into a nested Notebook channel.
• Fixes an issue where DM invitations would fail to appear without a full refresh.
• Fixes numerous unseen errors in both the back-end and the web client, which may improve web client startup performance.