TypeError in Web UI - Cannot read properties of undefined (reading 'length')

Description

Stack Trace:

TypeError: Cannot read properties of undefined (reading 'length')
    at Object.fn (http://127.0.0.1:4096/assets/session-Cg8YeoLd.js:14:50663)
    at Mk (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:6835)
    at Pl (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:6592)
    at Object._6 (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:5606)
    at get style (http://127.0.0.1:4096/assets/session-Cg8YeoLd.js:14:51075)
    at jL (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:24146)
    at Object.fn (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:23793)
    at Mk (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:6835)
    at Pl (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:6592)
    at Oe (http://127.0.0.1:4096/assets/index-Dl3PGFdp.js:2:1831)

Environment:

opencode: 1.2.20
Node: v24.12.0
npm: 11.6.2
OS: WSL Ubuntu 22.04.5 LTS (jammy)
Browser: Chrome auto-redirect

!  OPENCODE_SERVER_PASSWORD is not set; server is unsecured.

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  Web interface:      http://127.0.0.1:4096/

Plugins

superpower

OpenCode version

1.2.20

Steps to reproduce

Steps to Reproduce:
Run opencode web command in terminal, error appears immediately after Chrome browser opens

Screenshot and/or share link

Operating System

OS: WSL Ubuntu 22.04.5 LTS (jammy)

Terminal

WSL Ubuntu terminal

This issue might be a duplicate of existing issues. Please check:

Desktop UI crashes on load with Cannot read properties of undefined (reading 'id') in session bundle #16459: Very similar crash — TypeError: Cannot read properties of undefined in session-*.js bundle on Web UI startup with version 1.2.20. The stack traces both originate from the same asset file and crash the UI on load.

Same issue, thanks reporting as I just fix my self by GPT 5.4, so save me open another issue.

Root Cause

The crash is in packages/ui/src/components/text-shimmer.tsx lines 40 and 47:

const shimmerSize = createMemo(() => {
  const len = Math.max(props.text.length, 1)  // crashes if props.text is undefined
  ...
})
const shimmerDuration = createMemo(() => {
  const len = Math.max(props.text.length, 1)  // same
  ...
})

props.text is typed as string but can be undefined at runtime when the reactive value feeding it (e.g. i18n translation) hasn't resolved yet during initial evaluation.

Two PRs addressing this

PR fix(ui): guard TextShimmer against undefined text prop #16476 — minimal fix: props.text?.length ?? 0 (optional chaining)
PR fix(app): text-shimmer undefined length #16475 — structural fix: wraps in createMemo(() => props.text ?? "") and extracts shared len memo

Both are valid. PR #16475's approach is slightly more idiomatic for SolidJS (memoized fallback) and eliminates the duplicated len computation.

Same issue, Windows 11

Same issue, Windows 11 with oh my opencode

Same issue. Ubuntu 22.04

I see a fix was merged. Any idea when it will be released?

Same issue. Windows 11.

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TypeError in Web UI - Cannot read properties of undefined (reading 'length') #16473

Description

Plugins

OpenCode version

Steps to reproduce

Screenshot and/or share link

Operating System

Terminal

Root Cause

Two PRs addressing this

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TypeError in Web UI - Cannot read properties of undefined (reading 'length') #16473

Description

Description

Plugins

OpenCode version

Steps to reproduce

Screenshot and/or share link

Operating System

Terminal

Activity

github-actions commented on Mar 7, 2026

Eric-Guo commented on Mar 7, 2026

cyberprophet commented on Mar 7, 2026

Root Cause

Two PRs addressing this

HRronaldo commented on Mar 7, 2026

lzss433 commented on Mar 7, 2026

jeremyakers commented on Mar 7, 2026

PengMai1998 commented on Mar 7, 2026

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