desktop: user message bubbles regress in 2.0 — always blue, white-on-accent, unlike 1.18 #52028

Description

The user-message bubble in the Desktop chat regressed visually in 2.0. In 1.18 it was a neutral surface; in 2.0 it is always tinted blue, and in workspace sessions it becomes a saturated accent blue with fixed near-white text.

Every session is now classified as local or workspace and the bubble is styled per type:

• local, light: --v2-blue-100 background / --v2-blue-700 text
• local, dark: --v2-blue-1200 background / --v2-blue-300 text
• workspace: --v2-background-bg-accent background / --v2-text-text-contrast text

CSS: packages/session-ui/src/components/message-part.css (workspace rule ~1472-1477, local rules ~1479-1497). The attributes come from packages/app/src/session/timeline/virtualizer.tsx:643-644 (data-workspace-session / data-local-session). Because one of the two is always set, the generic neutral rule (--v2-background-bg-layer-01) is effectively unreachable.

In 1.18 (v1.18.33) the bubble was neutral: --v2-background-bg-layer-01/02 background with --v2-text-text-base text (packages/session-ui/src/components/message-part.css:1336-1383 in that tag). So the 1.18 -> 2.0 upgrade changes the chat from a calm neutral surface to a blue one, and the dialogue visually degrades.

This is most obvious with the default theme "OpenCode" (file oc-2.json, mapped to the label "OpenCode" in packages/ui/src/theme/context.tsx). It pins v2-blue-600 to #3b5cf6 and v2-text-text-contrast to near-white, so a workspace bubble is #3b5cf6 with #ffffff text (5.19:1):

White text on that indigo reads harshly, and all user messages in a workspace now form a bright blue wall. The underlying cause is structural: blue-600 is a mid-lightness step generated the same way for light and dark (generateV2HueScale() in packages/ui/src/theme/v2/resolve.ts), and the foreground is a fixed token rather than a contrast-aware one. The icon half of the same role is contrast-picked (packages/ui/src/theme/v2/foreground.ts:57), the text half is not. With other themes the same hardcoded pairing is unreadable (One Dark Pro: 1.11:1 - already reported separately in #50986).

Request: please restore the visual quality of the conversation area at least to the 1.18 level - either restore the neutral bubble, or make the accent-surface foreground contrast-aware (dark foreground on bright accent) and expose the token properly, so a theme cannot ship a bubble whose text cannot be read.

Expected Behavior

• User-message bubbles in Desktop 2.0 are at least as legible and visually calm as in 1.18.
• The accent surface is paired with a contrast-aware foreground, or the neutral layer-01 bubble is used by default and the strong accent is opt-in.

Actual Behavior

• All user-message bubbles are blue; workspace sessions use a saturated accent blue with fixed near-white text (#3b5cf6 / #ffffff in the default "OpenCode" theme).
• Other themes inherit a derived accent that can make the bubble text unreadable (see desktop: One Dark Pro workspace messages have low contrast #50986).

Steps to reproduce

1. Open OpenCode Desktop 2.0, go to Settings -> Appearance and select the theme "OpenCode".
2. Open or create a session whose directory is a workspace / worktree (in the project, not the main worktree).
3. Send a message and look at the user-message bubble: it is #3b5cf6 with white text.
4. For comparison, open a session in the project root (local session: dark navy #021945 with pale-blue text) and compare with the same message in 1.18 (neutral grey bubble).

Additional Context

• Related: desktop: One Dark Pro workspace messages have low contrast #50986 (workspace bubble low contrast in One Dark Pro), Desktop: theme switch does not apply text color in chat panel — text always stays white #42030 (chat text always stays white), TUI: unreadable mouse text selection in light mode (default opencode theme) #41281, Unreadable selected text selection in light themes #12861, Catppuccin macchiato is unreadable in desktop light mode #29629.
• The blue accent treatment was introduced by feat(desktop): update blue accent styling #47009 ("update blue accent styling") and fix(app): use worktree inventory for session accents #45506 (session accents from worktree inventory); the pairing is pinned by the e2e test packages/app/e2e/regression/workspace-accent.spec.ts, so it must be updated together with any fix.
• Reproducible consistently. Reproduced on 2.0.19; desktop: One Dark Pro workspace messages have low contrast #50986 confirmed the same tokens on 2.0.6 and 2.0.15, so the behavior is present across the whole 2.0 line.

Plugins

None.

OpenCode version

2.0.19 (Desktop).

Screenshot and/or share link

Attachments welcome from anyone on the current 2.0 build: a workspace-session bubble with the "OpenCode" theme (dark and light), next to the same bubble in 1.18.

Operating System

macOS 26 (Darwin 25.6.0, arm64); also reported on Windows 11 in #50986.

Terminal

OpenCode desktop app.