[BUG] Plugin/Skill "Update" button stays disabled even when a newer version exists upstream

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Environment

• Claude Desktop version: Claude 1.22209.0 (77c938) 2026-07-16T05:39:45.000Z
• OS: macOS - 26.5.2 (25F84)
• Affected: all installed plugins/skills, not isolated to one plugin

Description

The "Update" button in Settings → Plugins (and Skills) stays greyed out/disabled
even when the plugin's marketplace source has a materially newer release available.
This is not limited to one plugin — reproduced across every installed plugin/skill
checked so far.

<img width="977" height="730" alt="Image" src="https://github.com/user-attachments/assets/45d18a72-dc95-4bf4-ac9d-603be384a146" />

Expected

Update button should be enabled/clickable whenever installed version < latest
available version from the plugin's marketplace source.

Actual

Button stays disabled indefinitely; no in-app action (restart, toggle off/on,
re-click) changes state.

Suspected root cause

Desktop's version check appears to compare against a stale local marketplace
clone (~/.claude/plugins/marketplaces/<name>/) rather than re-fetching the
marketplace/remote state, so it incorrectly reports "already on latest."

Impact

Users have no visible way to know updates are available or to apply them
through the UI they're expected to use — silently stuck on stale plugin/skill
versions unless they know to drop into a terminal.

What Should Happen?

Expected

Update button should be enabled/clickable whenever installed version < latest
available version from the plugin's marketplace source.

Error Messages/Logs

## Actual
Button stays disabled indefinitely; no in-app action (restart, toggle off/on,
re-click) changes state.

Steps to Reproduce

Example repro

1. Install "Last30days" plugin from marketplace (last30days-skill).
2. Installed version shown in Desktop: 3.3.2
3. Upstream GitHub repo (https://github.com/mvanhorn/last30days-skill) latest

release: v3.16.0

1. Open Settings → Plugins → Last30days → Update button is disabled.
2. Same pattern reproduces on [list other plugins/skills you checked].

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude 1.22209.0 (77c938) 2026-07-16T05:39:45.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_