Unhide Chat (Expand) control is hidden for narrow windows
With recent changes to the Twitch channel interface on desktop browser, not only is chat hidden by default when opening the channel, but users can be stuck having chat hidden with no way to get it back easily.
If the user changes their window dimensions in such a way as to prompt Twitch to hide chat, they cannot bring it back without first stretching the window to be wide enough that Twitch deigns to display the "Expand" control at the edge of the page to unhide chat.
With recent changes, this control may not be accessible on windows displayed on Portrait-oriented monitors (e.g. 1200x1920, where a monitor is rotated vertically in Portrait orientation). This happens to me on Firefox with monitors in portrait --- I can only get chat back by first moving the window to a Landscape-oriented display and maximizing the window there, before moving it back.
The last few sets of interface changes have started adding a lot of frustrating behaviour for desktop users, but this one is particularly problematic as you can't undo the loss of chat in some scenarios.