docs: add troubleshooting for Claude Code plugin HTTPS clone failures

[hodorogandrei]

Summary

When installing chrome-devtools-mcp as a Claude Code plugin (from the official Anthropic marketplace or via /plugin marketplace add), the plugin system clones the repository using HTTPS (https://github.com/ChromeDevTools/chrome-devtools-mcp.git). In environments where outbound HTTPS connectivity to GitHub is restricted — such as servers behind corporate firewalls, restrictive proxy configurations, or hosts with port 443 blocked — this clone operation fails with a timeout:

chrome-devtools-mcp@claude-plugins-official: Failed to download/cache plugin chrome-devtools-mcp:
  Failed to clone repository: Cloning into '...'...
  fatal: unable to access 'https://github.com/ChromeDevTools/chrome-devtools-mcp.git/':
  Failed to connect to github.com port 443 after 136078 ms: Couldn't connect to server

This is a real-world scenario encountered on production Linux servers where SSH to GitHub (port 22) works but HTTPS (port 443) is blocked or unreliable. The Claude Code plugin marketplace (anthropics/claude-plugins-official) specifies the HTTPS URL as the plugin source, and users have no way to override this URL within the plugin system itself.

Changes

docs/troubleshooting.md

Added a new troubleshooting section Claude Code plugin installation fails with Failed to clone repository under Specific problems that documents:

• The exact error message users encounter, making it searchable
• Root cause explanation: restricted HTTPS connectivity, firewalls, proxy configs
• Workaround 1 — SSH redirect: Using git config --global url."git@github.com:".insteadOf "https://github.com/" to transparently redirect all GitHub HTTPS git operations to use SSH
• Workaround 2 — CLI installation: Using claude mcp add chrome-devtools --scope user npx chrome-devtools-mcp@latest to install the MCP server via npm/npx instead of git clone

README.md

Added a [!TIP] callout in the Claude Code Install as a Plugin section that cross-references the troubleshooting guide.

Motivation

The HTTPS clone URL for this plugin is defined in the Anthropic official plugin marketplace, not in this repository. Since users cannot change the marketplace URL configuration, the most actionable fix from this repository's side is to document the issue and provide clear workarounds.

Test plan

• npm run check-format passes (eslint + prettier)
• npm run gen produces no unexpected diff (auto-generated docs unchanged)
• Documentation-only change — no code, tool, or schema modifications
• Markdown anchor link in README TIP callout correctly references the troubleshooting section heading
• Both workaround commands verified in the environment where this issue was encountered

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[wolfib]

This is great! Thanks a lot!

[hodorogandrei]

This is great! Thanks a lot!

Thank you too! Will probably be back with other contributions if I discover further glitches while using this plugin.