Thistle — Toolkit for Claude by Nabil Uddin

Thistle adds four focused improvements to the Claude web app.
True-Black Theme
A pure-black #000 canvas with neutral elevation steps makes each panel feel like a distinct surface instead of another shade of grey. Coral remains the single accent colour.
You can disable the theme from the toolbar popup without disabling the extension.
Inline Usage Gauge
See your current session usage directly in the composer toolbar, between the + button and the model picker. It includes:
Your usage percentage
A progress bar that turns coral above 90%
A countdown to the next reset
Click the gauge to view both your 5-hour session window and weekly limit, including the reset time for each.
Usage figures come from the same endpoint Claude uses for its own limit warnings, so the numbers match what Claude reports.
Context Transfer
Send the open conversation to ChatGPT, Gemini, or Grok with one click.
Thistle formats the conversation as Markdown and opens it in the selected site’s composer in a new tab. It never presses Send, so you can review and edit the text first.
Useful for getting a second opinion—or continuing a conversation after reaching a Claude usage limit.
Markdown Export
Copy the open conversation to your clipboard or download it as a .md file.
Privacy
Thistle is designed to keep your data in your browser:
No account
No server
No analytics or telemetry
No remote code
Settings stored locally
Usage figures are read from Claude’s own API in your browser, using the session you are already signed in with. Conversation text is accessed only when you explicitly choose Transfer or Export. When transferring, it is sent only to the chatbot site you select.
Thistle runs only on claude.ai and the three chatbot sites it supports for context transfer.
Source code: https://github.com/leo-noble/Thistle
Thistle is not affiliated with, endorsed by, or connected to Anthropic. “Claude” is a trademark of Anthropic.