Firefox exposes removal operations for IndexedDB databases, object
stores, and records from the Storage panel. Route those actor requests
to LibWeb so DevTools can delete the selected data and receive the
update or clear event needed to refresh the panel.
The Storage panel expects storesUpdate messages after watched storage
changes. Summarize committed IndexedDB mutation logs into DevTools paths
and forward them through WebContent so Firefox can refresh database,
object-store, and record rows without polling.
Firefox's behaviour is less than ideal here. A lot of things don't
update automatically even inspecting a page in Firefox. Some
things (like new databases) won't show up until you fully refresh the
page. So that makes it a bit hard to know that we're doing things
correctly. As far as I can tell, we are at least behaving as well as
Firefox requires.
We do have one workaround: Firefox doesn't display record updates
without a manual refresh, and in fact any change messages for them show
up as rows in the host's database table. So for now, we filter them out
to avoid visual weirdness in the inspector.
Firefox asks the storage watcher for an indexed-db resource before it
shows IndexedDB entries in the Storage panel. Add an IndexedDB actor and
serialize the live LibWeb database registry on demand, so WebContent can
return the host tree and table rows without duplicating database state.
Use the LibWeb inspection helpers to read IndexedDB internals, and keep
the Firefox protocol shape in LibDevTools. WebContent only forwards the
serialized response over the existing DevTools IPC path.
Show native history menus when users right-click or long-press
the back and forward toolbar buttons. Populate entries from the
UI-process session history mirror, using saved history titles and
favicons when available and falling back to the URL and globe icon
otherwise.
Share the Qt base64 PNG icon helper so bookmark menus and navigation
history menus render stored favicons consistently.
Keep UI process session history authoritative across overlapping
fallback loads and traversals. WebContent can finish a superseded
history load with a live document matching the UI seed URL while its
local step, document state id, and Navigation API keys still describe
a temporary partial list.
Reconstruct the current entry around the UI-owned list in that case.
This avoids making the UI process adopt WebContent's incomplete
snapshot.
Track UI-started fallback loads by URL so unrelated navigations cannot
consume the pending seed state. Resolve deferred WebDriver completions
through the view registry so callbacks queued before a process swap do
not touch a destroyed view.
Add WebDriver coverage that waits for explicit UI/WebContent history
convergence after the relevant document events. The waits poll
observable history state instead of depending on timing.
Same-document navigations now commit synchronously in WebContent, while
the UI process mirror learns about them over asynchronous IPC. A stale
UI seed could be accepted back into a live non-initial document and
overwrite its latest entry, making queued traversals target unreachable
entries.
Share descriptor comparison helpers between LibWeb and LibWebView.
Reject stale top-level seeds against the active document latest entry,
and let the UI process adopt WebContent current snapshots when a seed is
rejected. Test-only session history dumps now first send WebContent
current state synchronously, so dumps observe the converged state.
Allow post-load UI seeds to carry UI-owned nested histories that the
freshly loaded top-level document has not reconstructed yet. Add unit
coverage for matching those seeds while still checking top-level state.
Use the LibWebView history mirror to preserve traversable session
history across WebContent process swaps. WebContent reports snapshots to
the UI process, and new renderers can be seeded from the mirror.
Browser back and forward now resolve through the UI-owned used history
steps. WebContent still runs the spec traversal path when the current
renderer has enough matching state to do so.
Handle canceled and no-op UI navigations without leaving speculative
history entries or pending WebDriver waits behind. Preserve traversal
precheck state across synchronous IPC shutdown, and avoid overwriting a
restored target entry's persisted scroll state before the document has
adopted that entry.
Firefox sends the same storage actor mutation requests for Web Storage
that it uses for cookies. Handle addItem, editItem, removeItem, and
removeAll for localStorage and sessionStorage actors.
Apply the changes through the browser-process storage jar and emit the
matching store update packets so the Storage panel stays current after a
DevTools-initiated edit.
Firefox keeps the Storage panel current by sending store update packets
when localStorage or sessionStorage changes. Forward successful Web
Storage mutations to the storage actors and emit the matching update or
clear packet.
Use listener IDs for storage updates so the local and session storage
actors can subscribe independently.
Firefox exposes localStorage and sessionStorage through the same
storage actor protocol used by cookies. Add matching resources for the
current tab so the Storage panel can list key/value pairs.
Read the values through WebContent rather than directly from the
browser process. Session storage lives in LibWeb, and using the same
path for both stores keeps the actor independent of the backing store.
Firefox keeps the Storage table current through storesUpdate messages
from the storage actor. Forward browser cookie change notifications to
the cookies actor and classify visible rows against a fresh cookie
snapshot.
The existing cookie-change notifications report cookies that are
relevant to a specific page, whereas DevTools wants all cookies
relevant for a host, so we end up having to provide two different sets
of cookies to `notify_cookies_changed()`.
Remove internals.loadTestVariants and the IPC forwarding that reported
variant metadata back to WebView. test-web now identifies WPT variants
during collection, so no loaded document needs to expose this test-only
hook.
Extend the existing DOM node inspection request with an options payload
and carry it through the browser process, WebView, IPC, and WebContent.
This lets later DevTools requests forward Firefox's top-level flags
without changing any inspected-node behavior yet.
Compositor recovery recreated contexts and replayed viewport sizes,
but it left the restarted helper with the default display metadata. A
recovered context could fall back to a 60 Hz timer instead of the
window's current display id and refresh rate until the frontend later
observed a screen change.
Store the display id in the shared view state, alongside the existing
maximum frame rate, and replay both values while restoring view state
after reconnect.
LibWebView owns the active page connection and bridges the DevTools
delegate to WebContent. Track picker state there, translate UI hover,
preview, pick, and cancel requests into hit-test IPC, and forward the
resulting node ids back through the DevTools callback.
Keeping the request bookkeeping in LibWebView also lets the platform UI
frontends share the same picker behavior.
Picking needs hit testing in the page process, where layout and event
targeting state live. Expose a small page-level query and WebContent IPC
entry point that returns the node id at a viewport position.
This lets DevTools ask WebContent what the picker is pointing at without
duplicating hit-test logic outside LibWeb.
Remember the preferred color scheme selected through the debug menu when
choosing the web view fallback background. Keep using an explicit forced
scheme even if the platform theme changes underneath it.
Seed the page background fallback from the platform color scheme before
WebContent has painted. Update the same fallback when the platform theme
changes, and when the preferred color scheme is forced through the debug
menu, so unpainted web view areas use the matching Canvas color.
Add IPC structures and requests for inspecting grid layout data from
WebContent.
WebView forwards the async replies to LibDevTools and exposes the grid
highlighter hooks used by the protocol layer.
Parse Firefox grid highlighter options in WebContent and store them with
the active grid highlight.
Track whether WebContent still needs a beforeunload check and let the
frontends immediately remove a tab or window when no prompt can be
shown. WebContent still receives the close request so pagehide, unload,
and cleanup steps can run.
When the visible view is removed immediately, keep detached ownership of
the WebContent page until it reports that the top-level traversable
closed. If no acknowledgement arrives, release detached ownership and
ask ProcessManager to shut down the unused WebContent process.
Notify the UI process with the solid canvas background color recorded
for the top-level document. This is the Canvas system color with the
effective document background composited over it, matching the color
used before normal painting.
Store that color on the view and use it when AppKit, Qt, and Gtk need
to fill areas exposed while an older bitmap is still on screen during a
window resize.
Register debug.process.show_web_content_process_id and use it to append
the active WebContent process ID to tab titles and tab tooltips in the
Qt, Gtk, and AppKit frontends.
Keep the stored page title unchanged so toggling the preference can
refresh each tab without waiting for a new title update.
Add a repeatable blocker-list option that reads local list files in the
browser process. The files are concatenated into one buffer and shared
with WebContent through the content blocker IPC path when view options
are applied.
Parse the buffer in WebContent and reject malformed UTF-8 without
replacing the currently installed rules.
Load the browser-generated crash page as a synthetic response for the
URL that was active when WebContent exited. This keeps the session
history entry, response URL, and created Document aligned with the same
navigation URL, so reload targets the original page without creating a
local document for an HTTP(S) history entry.
Suppress history metadata updates from the generated page and declare
an inert rel=icon. Fallback favicon loading now follows the HTML
condition that no link with the icon keyword exists, which avoids the
credentialed /favicon.ico request from the crashed origin.
Remember the zoom level for each host so that returning to a site
restores the zoom the user previously chose, matching what other
browsers have done for years.
When the user zooms in, zooms out, or resets the zoom, the resulting
level is written to Settings keyed by the current page's host. On
navigation, when a view's URL host changes, the stored level for the
new host is applied (or the global default if there is no override).
Per-host zoom changes are broadcast through the SettingsObserver so
that two tabs viewing the same host stay in sync as soon as the user
adjusts zoom in either one. Zoom changes from within the page (such
as internals.setBrowserZoom hook) and the WebContent restart path do
not persist, only user-initiated zoom changes do.
Previously, if search was disabled, entering non-URL text would just
silently drop the search query (and on Qt, we would reload the current
URL). We now detect that the query did not result in a navigation and
load an error page instead, which directs the user to enable search.
Generalize the backing store sharing abstraction into SharedImage, which
represents shared GPU memory independently of Skia and can be used to
share memory between different processes or different GPU contexts.
Now that LibIPC uses Mach ports for transport on macOS, IOSurface port
rights can be sent as regular IPC message attachments instead of through
a separate ad-hoc Mach message side-channel. Introduce
Web::SharedBackingStore that wraps either a MachPort (macOS) or
ShareableBitmap (other platforms) with IPC encode/decode support,
unifying backing store allocation into the existing
did_allocate_backing_stores IPC message.
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).