If the channel topic contains a newline, only the text up to that point gets displayed.

Multiple lines can be displayed in the full-size editor/info panel for the channel settings. I'm not going to make the topic bar below the tabs expand to multiple lines -- that's a horrible idea.

I'm not saying the newline should be rendered, but the official client converts it to a space, which I think is a decent idea.

If the topic is
"foo
bar",
It renders in the channel bar as
"foo bar"
in the web client and
"foo"
in Ripcord.

If anything, adding an indicator character at the end of the line to indicate that there's more to the topic than just the preview would be nice, because there's no way of knowing if the topic contains more text without explicitly checking it with the editor.