Like the new User Profile in DMs, include a new option to monitor threads or temporarily "pinned" channels.

Essentially, in the space where the new User Profile is in the DMs, add a similar feature that instead allows you to monitor a select number of or just a singular alternative chat or channel for better multitasking capabilities. This could be things like a temporarily "pinned channels" that are specific to you to monitor, or threads etc while you're in a DM. This could be helpful for things such as cross referencing, multitasking, moderation, etc.