Yeah it's a big change.
Workspace support is being worked on, it was half-implemented before, so we are taking a proper pass at it now.
For switching between sessions, can you tell me about your workflow from before? Because a tab can hold a session from any project. Are you saying that opening up a tab is too heavy of an action?
GitHub issues though has been a problem from us, we deal with a ton of noise/spam.
As for switching between sessions — it's the hierarchy that's lost on tabs.
in 1.17 I get basically a three-level hierarchy: project -> workspace -> session
I could say I rarely use more than one session per workspace (not including subagents), but switching between projects as totally separate contexts works good.
Tabs on the other hand are less organized, I can see them being fine for sessions in one project (although sidebar is more ergonomical on both desktop and mobile)
Keep in mind that this is coming from someone who has a live browser tab counter website: https://tabs.evtn.me/
I'm in the same boat as the parent comment. OpenCode has been my daily driver for a while (love the custom agents that I can easily create).
I'm working at the same time with 3-4 different projects and multiple tasks inside the same project.
Earlier with the sidebar I could easily go back to review previous chats, as I'm often working on multiple separate but somewhat connected tasks inside the same branch. Having just a tab for context is both visually limiting (personal preference probably).
The worktree support could use a configuration for setup, running and teardown (look at Jean for that - works pretty well) as a way to have more complex setup. In my case with Rails + Vue apps, each worktree would then have separate db, rails+vite ports, etc so that I can visually check multiple completed tasks in isolation.