Fix rendering issue in sidebar/topic, arising with multi-cabal mode

[Alexander Cobleigh]

for some reason the topic and parts of the user sidebar are getting greyed out when using multiple cabals. i'm not yet sure what the cause is, but it is clearly repeatable (and has been for some time)

in the image, the topic should be white, and i should be highlighted in the same manner as fleeky

in the image the content is escaping its boundary (likely from the cabal sidebar not having been accounted for)

in general, i want to have the active cabals be listed at the bottom, just above the input row, as in irssi. a change to that kind of layout could solve most of the listed issues :)

image of how irssi's channel layout could be reused for cabal's cabal layout