# DevTools features by host

> Which Lit DevTools features work under the Vite plugin, in the Chrome extension and in the Firefox extension.

Look up whether a DevTools feature works where you inspect the page. The panel is the same everywhere; what changes is what its host can reach.

## Hosts

* ![](/_astro/vite.Bs_r76O8.svg) **Vite plugin**: the panel docked in Vite DevTools or in its own tab at `/__lit/`, which the dev server serves even without Vite DevTools, on a page your Vite dev server serves.
* ![](/_astro/chrome.CRByiUFQ.svg) **Chrome extension**: [Lit Inspector](/guides/devtools/browser-extension/), a **Lit** tab in Chrome DevTools, on any http(s) page. It has no server behind it.
* ![](/_astro/firefox.1bWoP6pv.svg) **Firefox extension**: the same extension for Firefox, from Firefox Add-ons.

`lit-devtools dev` behaves like the extensions, plus **Export snapshot** and the MCP tools, because it runs a Node server. See [the CLI reference](/reference/cli/).

Where a feature depends on the browser rather than the host, the browser is named in brackets.

## Where it runs

|                     | ![](/_astro/vite.Bs_r76O8.svg) Vite plugin | ![](/_astro/chrome.CRByiUFQ.svg) Chrome extension | ![](/_astro/firefox.1bWoP6pv.svg) Firefox extension |
| ------------------- | ------------------------------------------ | ------------------------------------------------- | --------------------------------------------------- |
| Browsers            | Any (Chrome-only features marked)          | Chrome 114+                                       | Firefox 140+                                        |
| Pages               | Your dev server                            | Any http(s) page, production builds included      | Any http(s) page, production builds included        |
| Page CSP            | Same-origin scripts from Vite              | Not affected                                      | Not affected                                        |
| Turning it on       | `timeline: true` in the plugin options     | Per site, from the **Lit** tab                    | Per host, on every port, from the toolbar popup     |
| Frames              | Top page                                   | Top frame only                                    | Top frame only                                      |
| Needs a Node server |                                            |                                                   |                                                     |

## Components tab

| Feature                                                  | ![](/_astro/vite.Bs_r76O8.svg) Vite plugin                         | ![](/_astro/chrome.CRByiUFQ.svg) Chrome extension                  | ![](/_astro/firefox.1bWoP6pv.svg) Firefox extension |
| -------------------------------------------------------- | ------------------------------------------------------------------ | ------------------------------------------------------------------ | --------------------------------------------------- |
| Live component tree                                      |                                                                    |                                                                    |                                                     |
| Hover highlight and **Reveal**                           |                                                                    |                                                                    |                                                     |
| Pick an element on the page                              | With `sourceOverlay`                                               | Yes, any Lit element                                               | Yes, any Lit element                                |
| Properties, state, attributes                            |                                                                    |                                                                    |                                                     |
| Tasks, signals, controllers                              | Yes (controllers can be missing from minified builds)              | Yes (controllers can be missing from minified builds)              |                                                     |
| Native `#private` fields                                 | With `privateFields`                                               | On the plugin’s dev server, with `privateFields`                   | On the plugin’s dev server, with `privateFields`    |
| Source link and **Rendered at** link                     | With `sourceOverlay`                                               | Both, from the page’s sourcemaps and template text                 | Both, from the page’s sourcemaps and template text  |
| Reveal in the Elements panel                             |                                                                    |                                                                    |                                                     |
| Follow the Elements selection                            |                                                                    |                                                                    |                                                     |
| Lit tab in the Elements sidebar                          |                                                                    |                                                                    |                                                     |
| Open in the Sources panel                                |                                                                    |                                                                    |                                                     |
| Open in editor                                           | On a Vite dev server                                               | On a Vite dev server                                               |                                                     |
| Docs from Custom Elements Manifests                      | Linked by the page, found beside its scripts, or added in Settings | Linked by the page, found beside its scripts, or added in Settings |                                                     |
| HMR patch line and issues banner                         |                                                                    |                                                                    |                                                     |
| Request update                                           |                                                                    |                                                                    |                                                     |
| `$lit` and Store as global variable                      |                                                                    |                                                                    |                                                     |
| Flash updates                                            |                                                                    |                                                                    |                                                     |
| Empty-tree diagnosis (no runtime, duplicate Lit, iframe) |                                                                    |                                                                    |                                                     |

## Updates tab

| Feature                                    | ![](/_astro/vite.Bs_r76O8.svg) Vite plugin | ![](/_astro/chrome.CRByiUFQ.svg) Chrome extension | ![](/_astro/firefox.1bWoP6pv.svg) Firefox extension |
| ------------------------------------------ | ------------------------------------------ | ------------------------------------------------- | --------------------------------------------------- |
| Per-component counts, update time, reasons |                                            |                                                   |                                                     |
| Error attribution                          |                                            |                                                   |                                                     |
| Old and new values                         |                                            |                                                   |                                                     |
| Source and **Rendered at** links           | With `sourceOverlay`                       |                                                   |                                                     |

## Timeline tab

| Feature                                                          | ![](/_astro/vite.Bs_r76O8.svg) Vite plugin                              | ![](/_astro/chrome.CRByiUFQ.svg) Chrome extension                       | ![](/_astro/firefox.1bWoP6pv.svg) Firefox extension       |
| ---------------------------------------------------------------- | ----------------------------------------------------------------------- | ----------------------------------------------------------------------- | --------------------------------------------------------- |
| Record, stop, clear                                              |                                                                         |                                                                         |                                                           |
| Lifecycle, changed values, mouse, keyboard, custom events layers |                                                                         |                                                                         |                                                           |
| Render and Lit warnings layers                                   | Lit development builds only                                             | Lit development builds only                                             |                                                           |
| List and Tracks views, filters, span detail                      |                                                                         |                                                                         |                                                           |
| Custom layers from `addTimelineEvent`                            |                                                                         |                                                                         |                                                           |
| Export snapshot                                                  |                                                                         |                                                                         |                                                           |
| Performance tracks                                               | Yes (Chrome 134+: a Lit track group; other browsers: User Timing marks) | Yes (Chrome 134+: a Lit track group; Chrome 114–133: User Timing marks) | User Timing marks, in the Firefox Profiler’s Marker Chart |

## Settings, HMR and agents

| Feature                                      | ![](/_astro/vite.Bs_r76O8.svg) Vite plugin | ![](/_astro/chrome.CRByiUFQ.svg) Chrome extension | ![](/_astro/firefox.1bWoP6pv.svg) Firefox extension |
| -------------------------------------------- | ------------------------------------------ | ------------------------------------------------- | --------------------------------------------------- |
| Light and dark appearance                    |                                            |                                                   |                                                     |
| Plugin settings and live overrides           |                                            |                                                   |                                                     |
| Page preferences (flash, performance tracks) |                                            |                                                   |                                                     |
| About (versions, duplicate Lit, layers)      |                                            |                                                   |                                                     |
| Hot patching and the HMR indicator           |                                            |                                                   |                                                     |
| Deep links (`#tab=…&component=…`)            |                                            |                                                   |                                                     |
| Follows the page you switch to               | Across tabs, with a notice                 | The inspected tab, across navigations             | The inspected tab, across navigations               |
| MCP tools for coding agents                  |                                            |                                                   |                                                     |

## Related

[DevTools architecture](/concepts/devtools-architecture/)Where the panel runs, how it reaches the page, and where its settings live.

[Compatibility](/reference/compatibility/)Supported Node, Vite, Lit and browser versions.