io.github.easonwong-de/firefox-css-theme
NPM · FIREFOX-CSS-THEME
MCP for building, inspecting, and live-debugging Firefox CSS themes.
Available components
Last scanned (1 hour ago)
Scores higher than 95% of npm servers
Category Browser Automation
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security98
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- 43 of 128 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency97
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Cryptographically verified build provenance (signed, bound to easonwong-de/Firefox-CSS-Theme). View diagnostics → Pass
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 11 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability72
- AI-judged instruction clarity (good).Pass
- Tool/resource definitions use about 558 tokens (~50/item across 11 items; 11 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
- No destabilizing schema changes in the last 30 days.Pass
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety75
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- 0 of 2 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "remove_theme_css" implies "remove" and declares no destructiveHint at all, which the MCP spec reads as destructive by default. See how to fix → Fail
- An AI judge read all 11 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 2 Nov 26 0
- Stability: 0.97 → pass security
- 1 Nov 26 0
- Stability: pass → 0.97 functional
- 26 Oct 26 +15
- Malware scan: unverified → pass ▲ security
- Stability: 0.97 → pass security
- 25 Oct 26 −15
- Malware scan: pass → unverified ▼ security
- Stability: pass → 0.97 functional
- Package version: 0.3.4 → 0.3.5 functional
- 19 Oct 26 0
- Stability: 0.97 → pass security
- 18 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.
- 16 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.
- 14 Oct 26 +41
- Known CVEs: pass → unverified ▼ security
- Injection markers: unverified → pass ▲ security
- Dependency health: 0.86 → unverified ▼ functional
- Tool coverage: unverified → 100 ▲ functional
- Stability: unverified → 0.83 ▲ functional
- MCP protocol: unverified → pass ▲ functional
- Schema quality: excellent → good functional
- Package version: 0.3.3 → 0.3.4 functional
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 5 Nov 2026 · Analysed npm/firefox-css-theme@0.3.5
Provenance Verified
A signed build attestation was found and verified, binding this exact artifact to the source repository it claims to come from.
| Result | Verified |
|---|---|
| Ecosystem | npm |
| Reason | Verified |
| Discovered via | Registry attestation endpoint |
| Source repo | easonwong-de/Firefox-CSS-Theme |
| Certificate issuer | https://token.actions.githubusercontent.com |
| Certificate SAN | https://github.com/easonwong-de/Firefox-CSS-Theme/.github/workflows/publish.yml@refs/heads/main |
| Rekor log index | 3446503101 |
| Predicate type | SLSA build provenance https://slsa.dev/provenance/v1 |
| Subject digest | sha512:92db8fe2ac3eaba38b45890dbce577c43aaac9d2e3e970fb30be9664eb4688d842d630c021fbfc356968133d05bcc6e6339f68bda6958f05af4ad7423 |
Background: How many MCP packages publish verified provenance →
Dependencies 128 packages
| Packages resolved | 128 |
|---|---|
| Stale | 43 |
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
close_browser ~14
Close the running Firefox instance.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
customize_toolbar ~47
Activate or manage the Firefox Customise Toolbar mode in the browser chrome.
| Name | Type | Req | Description |
|---|---|---|---|
| action | string | – | Action to perform for customise toolbar mode ('enter' or 'exit'). Defaults to 'enter'. |
No output schema declared.
No examples provided.
execute_chrome_javascript ~40
Execute privileged JavaScript code in the Firefox chrome window context.
| Name | Type | Req | Description |
|---|---|---|---|
| script | string | yes | JavaScript code string to evaluate in the chrome context. |
No output schema declared.
No examples provided.
get_computed_styles ~57
Extract computed CSS property values for a Firefox UI chrome element.
| Name | Type | Req | Description |
|---|---|---|---|
| properties | array | – | Optional list of specific CSS property names. |
| selector | string | yes | CSS selector of the UI element (e.g. '#urlbar-background'). |
No output schema declared.
No examples provided.
get_ui_tree ~52
Retrieve the hierarchical DOM tree of the selected UI element in the Firefox chrome window.
| Name | Type | Req | Description |
|---|---|---|---|
| maxDepth | number | – | Maximum recursive depth to traverse. |
| rootSelector | string | – | CSS selector for the root element. |
No output schema declared.
No examples provided.
inject_theme_css ~62
Inject or replace a live stylesheet into the Firefox window.
| Name | Type | Req | Description |
|---|---|---|---|
| css | string | yes | CSS rules to inject. |
| id | string | – | Identifier for the stylesheet. |
| target | string | yes | Target scope: chrome for browser UI, or content for web pages. |
No output schema declared.
No examples provided.
launch_browser ~112
Launch a Firefox instance with chrome debugging capabilities enabled.
| Name | Type | Req | Description |
|---|---|---|---|
| binaryPath | string | – | Optional path to the Firefox executable binary. |
| headless | boolean | – | Optional flag to run Firefox in headless mode. |
| noToolbox | boolean | – | Optional flag to disable opening the Browser Toolbox. |
| profileName | string | – | Optional name of an existing Firefox profile. If omitted, uses an isolated temporary profile. |
| toolbox | boolean | – | Optional flag to open the Browser Toolbox. Defaults to true unless headless. |
No output schema declared.
No examples provided.
list_theme_css ~36
List all custom stylesheets currently injected into the Firefox window.
| Name | Type | Req | Description |
|---|---|---|---|
| target | string | yes | Target scope to list: chrome or content. |
No output schema declared.
No examples provided.
query_ui_elements ~48
Find elements in the Firefox UI chrome document matching a CSS selector.
| Name | Type | Req | Description |
|---|---|---|---|
| selector | string | yes | CSS selector to query in the chrome document (e.g. '#nav-bar', '#TabsToolbar'). |
No output schema declared.
No examples provided.
remove_theme_css ~49
Remove an injected stylesheet from the Firefox window.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | Identifier of the stylesheet to remove. |
| target | string | yes | Target scope of the stylesheet to remove: chrome or content. |
No output schema declared.
No examples provided.
take_ui_screenshot ~41
Capture a PNG screenshot of the Firefox browser chrome window or a specific UI component.
| Name | Type | Req | Description |
|---|---|---|---|
| selector | string | – | Optional CSS selector to screenshot a specific element. |
No output schema declared.
No examples provided.
How do I install the io.github.easonwong-de/firefox-css-theme MCP server?
io.github.easonwong-de/firefox-css-theme runs locally as an npm package, launched with npx -y firefox-css-theme. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · firefox-css-theme
claude mcp add easonwong-de-firefox-css-theme -- npx -y firefox-css-theme
What is the io.github.easonwong-de/firefox-css-theme MCP server?
io.github.easonwong-de/firefox-css-theme is an MCP server listed in the public MCP registry as io.github.easonwong-de/firefox-css-theme. MCP for building, inspecting, and live-debugging Firefox CSS themes. This page covers its npm package (firefox-css-theme).
Is the io.github.easonwong-de/firefox-css-theme MCP server safe to use?
io.github.easonwong-de/firefox-css-theme scores 92 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 5 November 2026. It declares no install or post-install scripts. Its build provenance is signed and verified. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the io.github.easonwong-de/firefox-css-theme MCP server expose?
io.github.easonwong-de/firefox-css-theme exposes 11 tools: launch_browser, close_browser, customize_toolbar, get_ui_tree, query_ui_elements, and 6 more. Their descriptions and schemas cost roughly 558 tokens of context every time the server is loaded.
Is the io.github.easonwong-de/firefox-css-theme MCP server still maintained?
io.github.easonwong-de/firefox-css-theme is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What licence is the io.github.easonwong-de/firefox-css-theme MCP server under?
io.github.easonwong-de/firefox-css-theme declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.