It would be nice to have the ability to create a special tab or mark a tab in a way so that all channels from a certain server are always opened in that tab.

Currently opening a text channel will open it in the current tab, this would open it in the tab assigned to the server if it exists. That way one can keep their tabs organised and doesn't have to switch to the tab of that server first before opening a different channel.

This is a very specific feature request that nobody else has asked for and it would require a significant amount of work. If multiple people request it, I will consider adding something like it, though I'm not sure exactly how it would work. (DMs? middle-clicking channels? multiple windows?)