I hate the new Yahoo mail. I hate that there's no way to revert to Basic or Classic. The message says "Your inbox has been redesigned with your preferences in mind." but that is obviously not true given how poorly it is designed and how you removed the option to revert to the old UI that actually worked.

The UI in new Yahoo mail looks overly busy and you give no options to actually make it easier to navigate and VIEW email, which is what it SHOULD be designed for. The left side panel takes up entirely too much space. I should have the option to hide or resize any vertical panel. But the side panel especially should not be defaulted to waste as much screen real estate as it does. The help article suggests opening contacts or starred messages in the side panel, but I don't want either of those. I want that side panel GONE. Whoever decided that was a good idea should be fired and never allowed to work in user design ever again.