Settings

Open them with ⌘,.

Reading

Setting
Theme	Automatic, Paper, Sepia, Night or Carbon. See Themes.
Typeface	System (SF) or Serif (New York).
Body text	12 to 20 pt. Also ⌘+ and ⌘−.
Show joins and parts	Folded into one line either way. Hide them in one channel with /joins or the toolbar button.
Nick changes only for people who spoke	Lurkers' renames stay out of the way.
Nicks in colour	Each person keeps the same colour. Mentions of you stay in blue.
Link previews	A card under the line with the page's title, summary and picture. Without the summary makes them one line shorter.
Images in the conversation	Images and videos. Keryx fetches links to find out what they are; videos never play by themselves.
Play animated GIFs	With Reduce Motion on in macOS, they stay still and play on hover.
Image size	Small, medium or large thumbnails.

Notifications

Setting
When you're mentioned	Your nick or one of your highlight words.
Private messages
Words that mention you besides your nick	Separated by spaces; whole words, ignoring case. Also /highlight add word.

Notifications never interrupt the conversation you're looking at. Mute one conversation with /mute or from the sidebar.

Away

Setting
Mark me away when I step away	On every network, and back when you return. An /away of your own is left alone.
When	When the screen locks, or after 5, 15 (default) or 30 minutes idle. Locking the screen or putting the display to sleep always counts.
Message	What others see. Empty says "Away".

Writing

Setting
Let others know while you type	Sends +typing, so others see your name as the next cue.

Files

Keryx uploads dropped files to the network's file host when it has one (draft/FILEHOST, as soju does), authenticated with your SASL credentials. Otherwise, or always if you turn that off, it uses your own uploader:

Setting
Custom uploader	A 0x0-style endpoint that takes a POST.
Form field	The multipart field for the file (file). Empty sends the file as the body.
Response	Where the link is: text (the body), location (the header) or json:key.path.
Token	Sent as Authorization: Bearer.

Privacy

Setting
Keep history on this Mac	So conversations open instantly; the server stays the source.
Privacy mode	Masks every nick with a stable pseudonym, in the sidebar and inside messages, for screenshots and streaming. ⌘⇧P.