These IPC methods should be expanded in the future to allow WebContent
to specify what UI elements should be kept/removed, for example, the
navigation UI.
Commit 84db5d8c1c introduced the ability
to load tests over an http:// URL instead of a file:// URL. Each time
this happens, we switch to a new WebContent process due to site
isolation. Our WebContent output capture was not handling this.
For some reason, this was causing a wide array of test failures and
timeouts. Often, the failures were accompanied by the content of the
files loaded over HTTP being dumped to stdout. It's not quite clear
what was going on here.
Instead of copying the Bitmap that wraps the IOSurface, we can just
present the IOSurface directly. This significantly reduces CPU usage in
the UI process, particularly at high refresh rates such as 120Hz where
it would saturate a full CPU core.
This is done by using CAMetalLayer and blitting the IOSurface to the
next drawable buffer, which handles triple buffering, locking the
IOSurface and vsync automatically. This also allows the Metal HUD to
work, but the only accurate stat is the frame intervals/FPS because
it's in the UI layer, not WebContent. However, that's still useful
to detect frame drops.
This will allow the UI to request WebContent to properly close the top
level traversable when closing a tab. For example, this allows the site
to ask if the user is sure they want to leave, closes WebSocket
connections and more.
This patch introduces a cookie cache in the WebContent process to reduce
blocking IPC calls when JS accesses document.cookie. The UI process now
maintains a cookie version counter per-domain in shared memory. When JS
reads document.cookie, we check whether we have a valid cached cookie by
comparing the current shared version to the last used version. If they
match, the cached cookie is returned without IPC.
This optimization is based on Chromium's shared versioning, in which it
was observed that 87% of document.cookie accesses were redundant. See:
https://blog.chromium.org/2024/06/introducing-shared-memory-versioning-to.html
Note that this cache only supports document.cookie, not HTTP Cookie
headers. HTTP cookies are attached to requests with varying URLs and
paths. The cookies that match the document URL might not match the
request URL, which we wouldn't know from WebContent. So attaching the
cached document cookie would be incorrect.
On https://twinings.co.uk, we see approximately 600 document.cookie
requests while the page loads. This patch reduces the time spent in
the document.cookie getter from ~45ms to 2-3ms.
This introduces a simple FileDownloader to download files in the UI
process from RequestServer. We use this to download the context menu
image - this download is likely to hit the disk cache.
These can get very large, exceeding the new IPC message size limits.
Instead of serializing them into messages (which was silly anyway)
we now send them as Core::AnonymousBuffer which uses shared memory.
When cookies change or expire, we currently send a list of all changed
cookies to all WebContent processes. We then filter that list in the
WebContent process for cookies that match the page's URL before sending
out cookie change events to JS.
We now perform this filtering in the UI process, so each WebContent
process only receives the cookies it would be interested in, if any.
This serves two purposes:
1. Less IPC chatter.
2. This will let each ViewImplementation know that its cookie value has
actually changed.
(2) is for an upcoming change that will introduce a cookie cache, and
will allow each view to know it should bust that cache.
Note that for this filtering to work, we must iterate ViewImplementation
instances rather than WebContentClient in order to have the view's URL.
We must then associate the IPC with the view's page ID.
No changes to the /cookiestore WPT subtests.
Add support for WPT test variants, which allow a single test file to be
run multiple times with different URL query parameters. Tests declare
variants using `<meta name="variant" content="?param=value">` tags.
When test-web encounters a test with variants, it expands that test into
multiple runs, each with its own expectation file using the naming
convention `testname@variant.txt` (e.g., `test@run_type=uri.txt`).
Implementation details:
- WebContent observes variant meta tags and communicates them to the
test runner via a new `did_receive_test_variant_metadata` IPC call
- test-web dynamically expands tests with variants during execution,
waking idle views after each test completion to pick up new work
- Use index-based test tracking to avoid dangling references when the
test vector grows during variant expansion
- Introduce TestRunContext to group test run state, and store a static
pointer to it for signal handler access
This enables proper testing of WPT tests that use variants, such as the
html5lib parsing tests (which test uri, write, and write_single modes)
and the editing/bold tests (which split across multiple ranges).
To avoid unnecessary IPC traffic, we now only send network response
bodies when a DevTools client is connected.
This requires tracking DevTools connection state in ViewImplementation
so we can propagate it to new WebContent processes created during
cross-site navigation.
Propagate the request initiator type (e.g., "xmlhttprequest", "fetch",
"script", "stylesheet") from LibWeb through the IPC layer to DevTools.
This enables Firefox DevTools to correctly identify XHR/fetch requests
and display appropriate cause types in the Network panel's "Initiator"
column.
This adds support for viewing request payloads (POST data) and response
bodies in the Firefox DevTools network panel.
Request bodies are captured when network requests start and passed
through IPC to the NetworkEventActor, which returns them via the
getRequestPostData protocol method.
Response bodies are streamed via a new IPC message as data is received,
accumulated in NetworkEventActor (with a 10MB size limit to prevent
memory issues), and returned via getResponseContent. Text content is
returned as UTF-8, while binary content (images, etc.) is base64.
Previously, console messages were sent using an index-based system where
DevTools would be notified of new message indices and then request them
in batches. This created synchronization issues during page navigation
when the WebContent process resets while DevTools still has stale index
state.
This changes to a push-based model where console messages are sent
immediately as resources when they are logged, matching how Firefox
DevTools handles console messages. Each message is pushed through IPC
and forwarded to DevTools as a "console-message" or "error-message"
resource.
This eliminates the need for index tracking in FrameActor and simplifies
the entire console message pipeline from WebContent through to DevTools.
When a page navigates, send document-event resources with
"will-navigate" and tabNavigated messages so Firefox DevTools
can follow along and clear the Network panel appropriately.
Hook ResourceLoader to emit network request lifecycle events through
IPC to the UI process, where FrameActor creates NetworkEventActor
instances that serialize requests using Firefox's Remote Debug Protocol.
The Network panel now shows requests with method, URL, status, MIME
type, size, and timing information. Several features remain stubbed
(POST data, response content, cause detection) marked with FIXMEs.
When multiple views share a WebContent process (e.g. parent and child
views created via window.open()), we need to notify ALL of them when
the process crashes, not just one.
Previously, each view would overwrite the single crash callback on
WebContentClient, so only the last view to initialize would be notified.
This adds WebContentClient::notify_all_views_of_crash() which iterates
over all registered views and notifies each one. Child views also now
propagate crashes to their parent, and can be disconnected between
tests to prevent stale crashes from affecting subsequent tests.
Clipboard handling largely has nothing to do with the individual web
views. Rather, we interact with the system clipboard at the application
level. So let's move these implementations to the Application.
This lets us avoid each UI needing to handle link clicks directly, and
lets actions stored in LibWebView avoid awkwardly going through the link
click callbacks to open URLs.
On macOS Tahoe, it is now recommended to show menu item icons. We use
system symbols for this now. Symbols do not have constant variable names
and must be found via the SF Symbols app.
The symbols chosen here were to match Safari as close as possible.
Global Privacy Control aims to be a replacement for Do Not Track. DNT
ended up not being a great solution, as it wasn't enforced by law. This
actually resulted in the DNT header serving as an extra fingerprinting
data point.
GPC is becoming enforced by law in USA states such as California and
Colorado. CA is further working on a bill which requires that browsers
implement such an opt-out preference signal (OOPS):
https://cppa.ca.gov/announcements/2025/20250911.html
This patch replaces DNT with GPC and hooks up the associated settings.
This migrates all duplicated context menus from the UIs to LibWebView.
The context menu actions are now largely handled directly in LibWebView,
with some UI-specific callbacks added to display e.g. confirmation
dialogs.
Actions that only ever apply to a specific web view are stored on the
ViewImplementation itself. Actions that need to be dynamically applied
to the active web view are stored on the Application.
WPT reference tests can add metadata to tests to instruct the test
runner how to interpret the results. Because of this, it is not enough
to have an action that starts loading the (mis)match reference: we need
the test runner to receive the metadata so it can act accordingly.
This sets our test runner up for potentially supporting multiple
(mis)match references, and fuzzy rendering matches - the latter will be
implemented in the following commit.
We currently have a single IPC to set clipboard data. We will also need
an IPC to retrieve that data from the UI. This defines system clipboard
data in LibWeb to handle this transfer, and adds the IPC to provide it.
This removes the old autoplay allowlist file in favor of the new site
setting. We still support the command-line flag to enable autoplay
globally, as this is needed for WPT.
The upcoming generated types will match those for pseudo-classes: A
PseudoElementSelector type, that then holds a PseudoElement enum
defining what it is. That enum will be at the top level in the Web::CSS
namespace.
In order to keep the diffs clearer, this commit renames and moves the
types, and then a following one will replace the handwritten enum with
a generated one.
When we inspect a DOM node, we currently serialize many properties for
that node, including its layout, computed style, used fonts, etc. Now
that we aren't piggy-backing on the Inspector interface, we can instead
only serialize the specific information required by DevTools.
These commands are used for the "Edit As HTML" feature in DevTools. This
renames our existing HTML getter IPC to indicate that it is for outer
HTML. DevTools will need a separate inner HTML getter.
Site isolation is a common technique to reduce the chance that malicious
sites can access data from other sites. When the user navigates, we now
check if the target site is the same as the current site. If not, we
instruct the UI to perform the navigation in a new WebContent process.
The phrase "site" here is defined as the public suffix of the URL plus
one level. This means that navigating from "www.example.com" to
"sub.example.com" remains in the same process.
There's plenty of room for optimization around this. For example, we can
create a spare WebContent process ahead of time to hot-swap the target
site. We can also create a policy to keep the navigated-from process
around, in case the user quickly navigates back.
