[FEATURE]: Don't deprecate multi-project/session layout + stabilize reading area in new tab layout (1.18.3) #37527

Describe the enhancement you want to request

Important clarification: The old layout is still available and can be toggled on, and the team has not explicitly said it will be removed. So this request is not about "restoring" the old layout — it's about asking that the old, orchestrator-friendly layout not be abandoned / deprecated, since all current momentum — from community discussion to repo activity — is now on the new tab layout. Either keeping the old layout as a maintained, first-class option, or bringing its multi-project/orchestrator capabilities into the new layout, would resolve the concerns below.

Context: I'm a long-time OpenCode user on large-screen setups, running multiple projects in parallel. After upgrading to 1.18.3 and trying the new tab layout, my overall impression is that the UI looks "cleaner," but my actual productivity and reading experience are noticeably worse than in the old layout. Below are three concrete problems, followed by a note on design direction.

1. Wasted space on the left — significantly lower information density on large screens

In the old layout, the left sidebar showed the project and session list. For me it was a "command center":

• I could see multiple projects at once.
• All sessions under each project were visible at a glance.

In the new layout:

• The left-side project/session view is gone.
• Sessions only appear as top tabs; the main content area is centered with a capped width, leaving large empty space on the left.

Impact on me:

• Screen real estate that could surface projects, sessions, and Agent status is now essentially empty and unused.
• When working across multiple projects in parallel, there's no "overview" area — I have to scan horizontally across a limited set of tabs, which noticeably increases cognitive and interaction cost.

The old layout already handles this well; please keep it available, or bring an equivalent project / session / Agent overview into the new layout.

2. The project → session hierarchy has been flattened — multi-project workflows are weakened

A key strength of the old layout was its two-level structure:

• Level 1: projects.
• Level 2: the sessions/tasks under a given project.

This fit my actual workflow very well — maintaining multiple projects at once, and opening different sessions under each for planning, implementation, refactoring, documentation, etc.

The new layout flattens these sessions into the top tabs:

• The project/session hierarchy is weakened in the UI.
• Sessions visually become a string of tabs; project ownership and overall structure now have to be maintained by naming and memory.

Impact on me:

• It's hard to see at a glance "which sessions are currently active under project X."
• Across parallel projects, there's no clear "project → session" tree view, which noticeably reduces my ability to manage and supervise overall state.

The old layout already provides this two-level structure; please don't deprecate it, and/or add an equivalent "project + session tree" side view to the new layout for high-concurrency scenarios.

3. The centered session area causes the left-alignment line to keep shifting — poor reading experience

In the new layout, the session content area:

• Has a width cap and is center-aligned.
• Shifts left/right whenever the right-hand review panel is opened or closed.

This directly hurts reading of text and code:

• Reading depends on a stable left alignment line, and that line now moves every time the review panel toggles.
• During long sessions of supervising Agent output, or reviewing long conversations / diffs, this constant re-anchoring of gaze causes clear fatigue and makes it easy to miss or misread content.

I'd hope:

• The left edge of the main session area stays fixed, regardless of the right panel toggle.
• Consider a "high-density / stable reading mode" that prioritizes keeping the content area's position and width stable.

A note on design direction

The three points above reflect concrete problems — space utilization, information structure, and reading rhythm — all drawn from real daily usage.

In terms of use case, my mental model is closer to "an orchestrator directing multiple coding agents in parallel":

• I'm not just writing code in a single project — I'm scheduling multiple projects and multiple task lines at once.
• I need a "console"-style view to manage project / session / Agent state, not just a centered single-session chat UI.

The old two-level project/session layout with a vertical left-side sidebar fits this need very well. The new tab layout feels more oriented toward a "single project, few sessions" model.

I understand the focus has shifted to the new layout, and I'm not asking to freeze the product on the old one. What I'm asking is simply that the orchestrator-friendly layout not be abandoned — either by keeping the existing old layout as a maintained, first-class option, or by making sure the new layout eventually gains an equivalent multi-project/session overview plus a stable reading area. As it stands today, the new layout is a productivity downgrade rather than an upgrade for the multi-project, multi-Agent use case.

I really appreciate OpenCode's positioning on agent capabilities and ecosystem, and I'm happy to keep using it and giving feedback. I hope this is useful input for future design and configuration decisions.

(Related: #37508 covers the narrower "workspaces are gone" symptom; this issue is about the broader multi-project/orchestrator UX, and about not deprecating the layout that supports it.)