channel list randomly moves channels from place to place

[gdamjan]

when communi is started this[1] weird behaviour happens, pressing ctrl-l to go to the next channel with new messages, some channels would jump to another place. sometimes more of them (in this case I only caught one).

[1] look at the openwrt channel, how it jumps down. I only press ctrl-l several times
https://imgur.com/a/Amzoc