Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/1226
Related commit:
- 9eb455ab5e
In the previous commit, the element picker dialog was
isolated from the page content. This commit is to also
isolate the svg layers from the page content.
With this commit, there is no longer a need for an anonymous
iframe and the isolated world iframe is now directly
embedded in the page.
As a result, pages are now unable to interfere with any
of the element picker user interface. Pages can now only
see an iframe, but are unable to see the content of that
iframe. The styles applied to the iframe are from a user
stylesheet, so as to ensure pages can't override the
iframe's style properties set by uBO.
This commit fixes deleting all entries when cloud
storage usage is beyond allowed limit.
The issue would prevent pushing new data well within
quota limit because the old data beyond limit was
never removed in the first place.
Cloud storage is a limited resource, and thus it
makes sense to support data compression before
sending the data to cloud storage.
A new hidden setting allows to toggle on
cloud storage compression:
name: cloudStorageCompression
default: false
By default, this hidden setting is `false`, and a
user must set it to `true` to enable compression
of cloud storage items.
This hidden setting will eventually be toggled
to `true` by default, when there is good confidence
a majority of users are using a version of uBO
which can properly handle compressed cloud storage
items.
A cursory assessment shows that compressed items
are roughly 40-50% smaller in size.
The pseudo user styles code served only browsers based
on Chromium 65 and earlier -- Chromium 66 supports
native user styles and was first released more than two
years ago.
In Chromium-based browsers, the pseudo user styles code
is being unconditionally injected in every page/frame
just in case the browser is version 65 or earlier.
Removing pseudo user styles reduce uBO's main content
script in Chromium-based browsers by more than 20K.
Related thread:
- https://github.com/NanoAdblocker/NanoCore/issues/348#issuecomment-653646507
Related discussion:
- https://bugzilla.mozilla.org/show_bug.cgi?id=1652925
It's not clear the code here will fix the reported
issue, but I did identify that the subframe
dictionary of a very long-lived web page can
theoretically grow unbound.
Related feedback:
- https://www.reddit.com/r/uBlockOrigin/comments/hbea3z/
It appears the implementation of the `disable_non_proxied_udp`
setting changed in Chromium, leading to WebRTC becoming
wholly unfunctional. Fall back to use `default_public_interface_only`
in Chromium-based browsers.
The old "classic" popup panel will still be used
when at least one of the following is true:
- advanced setting `uiFlavor` is set to `classic`; or
- the browser is Chromium 65 or older; or
- the browser is Firefox 67 or older
The default configuration of the new popup panel
at installation time is to show the power button,
statistics and the basic tool icons, i.e. access
to dashboard, logger, pickers.
For existing installations, the new popup panel
will be configured by respecting the existing
configuration of the classic one.
The new popup panel is currently already in use
on Firefox for Android, and the visual redesign
was made according to suggestions and feedback
from <https://github.com/brampitoyo> to be
optimal for Firefox for Android.
The new popup panel will allow closing the following
pending issues:
- https://github.com/uBlockOrigin/uBlock-issues/issues/255
- https://github.com/uBlockOrigin/uBlock-issues/issues/178
Related commit:
- 2ac288397c
Instead of having the `localStorage` data being accessed
from different locations, all accesses are now funnelled
to the main process.
Doing so simplifies the code in auxiliary processes and
also remove the need for browser.storage.local.onChanged()
listeners.
No longer using an onChanged() listener also happens to
remove spurious warnings from the Firefox console.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/911
Since cname-uncloaking is available only on Firefox
at the moment, the fix is relevant only to Firefox.
By default uBO will no longer cname-uncloak when it
detects that network requests are being being proxied.
This default behavior can be overriden by setting the
new advanced setting `cnameUncloakProxied` to `true`.
The new setting default to `false`, i.e. cname-uncloaking
is disabled when uBO detects that a proxy is in use.
This new advanced setting may disappear once the
following Firefox issue is fixed:
- https://bugzilla.mozilla.org/show_bug.cgi?id=1618271
***
New procedural cosmetic operator: `:remove()`
Related issue:
- https://github.com/gorhill/uBlock/issues/2252
The purpose is to outright remove elements from the
DOM tree. Since `:remove()` is an "action" operator,
it must only be used as a trailing operator (just
like the `:style()` operator).
AdGuard's cosmetic filter syntax `{ remove: true; }`
will be converted to uBO's `:remove()` operator
internally.
***
New procedural cosmetic operator: `:upward(...)`
The purpose is to lookup an ancestor element.
When used with an integer argument, it is synonym of
`:nth-ancestor()`, which will be deprecated and which
will no longer be supported once no longer used in
mainstream filter lists.
Filter lists maintainers must only use `:upward(int)`
instead of `:nth-ancestor(int)` once the new operator
become available in all stable releases of uBO.
`:upward()` can also accept a CSS selector as argument,
in which case the nearest ancestor which matches the
CSS selector will be selected.
The stricter mode `disable_non_proxied_udp` is preferable
to `default_public_interface_only` to prevent local IP
address leakage through WebRTC.
This mode is properly supported since Firefox 70, so the
less strict `default_public_interface_only` will now be
used only for Firefox 69 and older.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/899
browser.storage.local is now used to store non-critical
local settings.
These settings are all collated under the key
`localStorage`, and vAPI.localStorage is an API to
handle access to these values stored under this key.
vAPI.localStorage.getItem() is still synchronous but
its purpose is to return internally cached values --
this minimizes code changes throughout uBO.
This is to fix the rendering of the menu entry in
Firefox Fenix, which displays both the icon title
and badge text as a menu entry:
Before the fix:
uBlock Origin (76) 76
After the fix:
uBlock Origin 76
The badge text will still be part of the icon title
when the icon badge is disabled by the user or when
the platform does not supprt browserAction.setIcon()
(as is the case on current Firefox for Android).
Advanced setting `cnameAliasList` has been removed.
New advanced settings:
cnameUncloak:
Boolean
Default value:
true
Description:
Whether to CNAME-uncloak hostnames.
cnameIgnoreExceptions:
Boolean
Default value:
true
Description:
Whether to bypass the uncloaking of network requests
which were excepted by filters/rules. This is
necessary so as to avoid undue breakage by having
exception filters being rendered useless as a result
of CNAME-uncloaking.
For example, `google-analytics.com` uncloaks to
`www-google-analytics.l.google.com` and both hostnames
appear in Peter Lowe's list, which means exception
filters for `google-analytics.com` (to fix site
breakage) would be rendered useless as the uncloaking
would cause the network request to be ultimately
blocked.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/780
Related commit:
- https://github.com/gorhill/uBlock/commit/3a564c199260
This adds two new advanced settings:
- cnameIgnoreRootDocument
- Default to `true`
- Tells uBO to skip CNAME-lookup for root document.
- cnameReplayFullURL
- Default to `false`
- Tells uBO whether to replay the whole URL or just
the origin part of it.
Replaying only the origin part is meant to lower
undue breakage and improve performance by avoiding
repeating the pattern-matching of the whole URL --
which pattern-matching was most likely already
accomplished with the original request.
This commit is meant to explore enabling CNAME-lookup
by default for the next stable release while:
- Eliminating a development burden by removing the
need to create a new filtering syntax to deal with
undesirable CNAME-cloaked hostnames
- Eliminating a filter list maintainer burden by
removing the need to find/deal with all base
domains which engage in undesirable CNAME-cloaked
hostnames
The hope is that the approach implemented in this
commit should require at most a few unbreak rules
with no further need for special filtering syntax
or filter list maintance efforts.
This fixes the ability to block when a hostname
had to be cname-resolved the first time it was
encountered. The result being cached allowed
the subsequent requests to be correctly blockable.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/780
- Handle DNS lookup failure
- Skip DNS lookup for non network-based URLs
- Benchmark code to be able to provide an estimate
based on objective measurements regarding added
overhead when DNS lookup is enabled
(quick answer: a complete non-issue)
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/780
New webext permission added: `dns`, which purpose is
to allow an extension to fetch the DNS record of
specific hostnames, reference documentation:
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dns
The webext API `dns` is available in Firefox 60+ only.
The new API will enable uBO to "uncloak" the actual
hostname used in network requests. The ability is
currently disabled by default for now -- this is only
a first commit related to the above issue to allow
advanced users to immediately use the new ability.
Four advanced settings have been created to control the
uncloaking of actual hostnames:
cnameAliasList: a space-separated list of hostnames.
Default value: unset => empty list.
Special value: * => all hostnames.
A space-separated list of hostnames => this tells uBO
to "uncloak" the hostnames in the list will.
cnameIgnoreList: a space-separated list of hostnames.
Default value: unset => empty list.
Special value: * => all hostnames.
A space-separated list of hostnames => this tells uBO
to NOT re-run the network request through uBO's
filtering engine with the CNAME hostname. This is
useful to exclude commonly used actual hostnames
from being re-run through uBO's filtering engine, so
as to avoid pointless overhead.
cnameIgnore1stParty: boolean.
Default value: true.
Whether uBO should ignore to re-run a network request
through the filtering engine when the CNAME hostname
is 1st-party to the alias hostname.
cnameMaxTTL: number of minutes.
Default value: 120.
This tells uBO to clear its CNAME cache after the
specified time. For efficiency purpose, uBO will
cache alias=>CNAME associations for reuse so as
to reduce calls to `browser.dns.resolve`. All the
associations will be cleared after the specified time
to ensure the map does not grow too large and too
ensure uBO uses up to date CNAME information.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/759
If for some reasons the launch code throws, uBO could
find itself in permanent suspend mode, thus preventing
web pages from loading in Firefox.
Though uBO should not have exceptions thrown during
it's initialization code, this commit will ensure
uBO complete its initialization process should it
ever happen for whatever reason.
Tabless network requests were bypassing uBO's
onBeforeRequest's listener when in suspended
mode. Suspend mode occurs during the time the
filter lists are all reloaded.
Regression from:
- 1dfdc40e09 (diff-d04c15ee6bff6a6269c6aee25a7c7522R1122)
Related commit:
- 87d0e456f1
Ensure that the code which depends on extending
`vapi-client.js` is ready to deal with
`vapi-client-extra.js` failing to load.
These spurious error messages can occur when a
extension framework API method return a
rejected Promise. In uBO the results of
browserAction methods is not used so it can be
safely discarded.
Related feedback:
- https://www.reddit.com/r/uBlockOrigin/comments/d6zbqv/
For static filter `popup` filter purpose, the URL of the
embedded frame from which the popup was launched will
be used in the matching algorithm.
... from platform-independent code.
This should complete the de-chromiumification of
uBO. Next step will be to swap the content of the
`platform/chromium` and `platform/firefox`
folders so as to reflect that Firefox is the
natural platform for uBO.
Little-used code from vapi-client.js has been moved
to vapi-client-extra.js. Given that vapi-client.js
is injected in all web pages, this means less dead
code being injected in all pages.
Swathes of code in vapi-client.js was used only in
a few very specific cases, such as when the logger's
DOM inspector is opened or when the "Filter lists"
pane in the dashboard is opened -- and thus to avoid
that little used code to be loaded in every web page
unconditionally, it has been moved to its own
separate file, vapi-client.extra.js.
vapi-client-extra.js is loaded declaratively or
programmatically only where needed.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/710
Messages from unprivileged ports (i.e. from content scripts)
are no longer relayed to message handlers which are to be
strictly used to execute privileged code.
The last remaining case of unprivileged messages which
should be converted into a privileged ones will be taken
care of when the following issue is fixed:
- https://github.com/gorhill/uBlock/issues/3497
Related feedback:
- https://www.reddit.com/r/uBlockOrigin/comments/cmh910/
Additionally, the `3p` rule has been made distinct from
`3p-script`/`3p-frame` for the purpose of
"Relax blocking mode" command.
The badge color will hint at the current blocking mode.
There are four colors for the four following blocking
modes:
- JavaScript wholly disabled
- All 3rd parties blocked
- 3rd-party scripts and frames blocked
- None of the above
The default badge color will be used when JavaScript is not
wholly disabled and when there are no rules for `3p`,
`3p-script` or `3p-frame`.
A new advanced setting has been added to let the user choose
the badge colors for the various blocking modes,
`blockingProfileColors`. The value *must* be a sequence of
4 valid CSS color values that match 6 hexadecimal digits
prefixed with`#` -- anything else will be ignored.
Related Chromium issue:
- https://bugs.chromium.org/p/chromium/issues/detail?id=985759
By expressly restricting JavaScript execution to only code
from the extension package, this explicitly tells code reviewer
that uBO can't execute remote code.
I also had to add `object-src 'self'`, otherwise Chromium
refused to load the extension with the following error message:
> 'content_security_policy': CSP directive 'object-src' must be specified
`object-src 'self'` is the default value.
This works only for platforms supporting the return of
Promise by network listeners, i.e. only Firefox at this
point.
When filter lists are reloaded[1], there is a small
time window in which some network requests which should
have normally been blocked are not being blocked
because the static network filtering engine may not
have yet loaded all the filters in memory
This is now addressed by suspending the network request
handler when filter lists are reloaded -- again, this
works only on supported platforms.
[1] Examples: when a filter list update session
completes; when user filters change, when
adding/removing filter lists.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/371
By default, no specific keyboard shortcut is predefined,
this will have to be assigned by the user. The command
name in English is "Toggle blocking profile".
The default behavior is to toggle down according to one
of the following scenarios.
a) If script execution is disabled through the no-scripting
switch, the no-scripting switch will be locally toggled
so as to allow script execution. The page will be
automatically reloaded.
b) If script execution is not blocked but the 3rd-party
script and/or frame cells are blocked, local no-op rules
will be set so as to no longer block 3rd-party scripts
and/or frames. The page will be automatically reloaded.
Given this, it may take more than one toggle down command
to reach the lowest blocking profile, which is one where
JavaScript execution is not blocked and 3rd-party scripts
and frames resources block rules, if any, are bypassed
with local no-op rules.
TODO: At this point, I haven't yet decided whether
toggling from the lowest profile should restore the
original highest blocking profile.
Regression from:
- 62387fb87a
Repro steps were:
- Open the logger
- Navigate to `https://news.ycombinator.com/`
- Select an element using the element picker
- Click "Preview"
An attribute selector used internally by uBO to
hide targeted nodes was being reported in the
logger.
I had exceptions thrown by that code once in a while,
about the `port` object not being connected; possibly
occurs only when using dev tools with breakpoints
in uBO's code. Even if this can be reproduced randomly
only when debugging uBO, it costs nothing to add code
in there to handle exceptions.
Related issue:
- https://github.com/gorhill/uBlock/issues/127
Additionally, the extended exception filters in the
logger will be rendered with a line-through to more
easily distinguish them from non-exception ones.
Also, opportunistically converted revisited code to
ES6 syntax.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/550
Related Chromium issue (I can't access it):
- https://bugs.chromium.org/p/chromium/issues/detail?id=957866
Findings so far: affects browsers based on Chromium 74.
I could not reproduce the issue with either Chromium 73 or
Google Chrome 75.
This commit is a mitigation: to prevent sites from using
uBO's internal WAR secret for tracking purpose. A secret
can be used for at most one second, after which a new secret
is generated.
The original issue related to the implementation of
secret-gated web accessible resources is:
- https://github.com/gorhill/uBlock/issues/2823
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/548
The fix applies only to Chromium-based browsers -- a
`X-DNS-Prefetch-Control` header[1] will be unconditionally
injected when uBO's "Disable pre-fetching" setting is
enabled (it is by default).
This is a mitigation, this does not completely fix the issue
of the setting "Disable pre-fetching" being disregarded on
Chromium-based browsers when sites use
`preconnect`/`preload`.
[1] https://developer.mozilla.org/docs/Web/HTTP/Headers/X-DNS-Prefetch-Control
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/416
The Chromium version of uBO has declared `unlimitedStorage` since the
extension was first published in 2014. Declaring this permission in
Firefox brings uBO inline with the Chromium version. I suspect some
reported errors could be caused by IndexedDB eviction due to the lack
of `unlimitedStorage` permission.
Additionally, a timeout has been added when uBO tries to access its
indexedDB storage. It's unclear whether this will help with the
mentioned related issue though, the root cause is still to be
identified.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/409
By default `indexedDB` is used in Firefox for purpose of cache storage
backend.
This commit allows to force the use of `browser.storage.local` instead
as cache storage backend. For this to happen, set `cacheStorageAPI` to
`browser.storage.local` in advanced settings.
Additionally, should `indexedDB` not be available for whatever reason,
uBO will automatically fallback to `browser.storage.local`.
The motivation is to address the higher peak memory usage at launch
time with 3rd-gen HNTrie when a selfie was present.
The selfie generation prior to this change was to collect all
filtering data into a single data structure, and then to serialize
that whole structure at once into storage (using JSON.stringify).
However, HNTrie serialization requires that a large UintArray32 be
converted into a plain JS array, which itslef would be indirectly
converted into a JSON string. This was the main reason why peak
memory usage would be higher at launch from selfie, since the JSON
string would need to be wholly unserialized into JS objects, which
themselves would need to be converted into more specialized data
structures (like that Uint32Array one).
The solution to lower peak memory usage at launch is to refactor
selfie generation to allow a more piecemeal approach: each filtering
component is given the ability to serialize itself rather than to be
forced to be embedded in the master selfie. With this approach, the
HNTrie buffer can now serialize to its own storage by converting the
buffer data directly into a string which can be directly sent to
storage. This avoiding expensive intermediate steps such as
converting into a JS array and then to a JSON string.
As part of the refactoring, there was also opportunistic code
upgrade to ES6 and Promise (eventually all of uBO's code will be
proper ES6).
Additionally, the polyfill to bring getBytesInUse() to Firefox has
been revisited to replace the rather expensive previous
implementation with an implementation with virtually no overhead.
The environment flavor is used to by uBO to for self-configuration.
For users with spoofed UA at the `about:config` level, this might
cause uBO to misconfigure itself. Avoid UA and strictly rely on
browserInfo() for looking up environment parameters.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/407
Both flavors will be stitched together into a single
`vapi-qebrequest.js` file.
The decision of which flavor to use will be made at runtime,
according to the browser environment.
Those spurious disconnections have been observed to occur at
uBO's launch time.
Related issue:
- https://github.com/uBlockOrigin/uBlock-issues/issues/403
I have observed that this fixes an issue observed on Firefox 64
(current stable).
The reported Waterfox issue *may* be fixed as a result. If not,
the issue he still considered fixed as Waterfox is not
officially supported.
Related issues:
- https://github.com/uBlockOrigin/uBlock-issues/issues/194
This is a first iteration, which purpose is to merely allow
uBO to load properly. Many things are known to not work,
quite probably due to the early Thunderbird support of the
WebExtensions framework.
Permission which had to be removed:
- contextMenus
Manifest entries which had to be removed:
- commands
- sidebar_action
uBO's webRequest listeners are not being called when loading a
feed item in the preview pane, *except* for resources fetched
from embedded iframes.
uBO appears to function properly when a feed item is opened in
its own tab.
Performance-related work: the logger data has been decoupled
from the DOM -- inspired from CodeMirror's way of efficiently
handling large amout of text data.
This decoupling now makes the logger highly efficient CPU- and
memory-wise, and open the way to more possibilities.
Ability to configure some aspect of the logger behavior and
visuals:
- The hard-coded limit of 5000 entries has been
removed and is now replaced with a variety of
user-configurable settings to enforce the discarding of
logger entries.
- Some columns in the logger output can now be hidden.
The filter list look-up feature has been merged into the
existing overlay dialog used to create URL rules or static
filters, as an entry in a new "Details" pane.
Other issues addressed during refactoring:
- https://github.com/uBlockOrigin/uBlock-issues/issues/280
- https://github.com/gorhill/uBlock/issues/1999
The minimum version supported on Firefox has been bumped
up to 55.0.
Squashed commit of the following:
commit 6a8473822537636ac54d5dabdb14472114bb730b
Author: Raymond Hill <rhill@raymondhill.net>
Date: Mon Aug 6 10:56:44 2018 -0400
remove remnant of snappyjs and spurious instruction
commit 9a4b709bee97d3cc2235fab602359fa5953bdb46
Author: Raymond Hill <rhill@raymondhill.net>
Date: Mon Aug 6 09:48:58 2018 -0400
make cache storage compression optionally available on all platforms
New advanced setting: `cacheStorageCompression`. Default is `false`.
commit 22ee6547f2f7c9c5aefe25dea1262a1b31612155
Author: Raymond Hill <rhill@raymondhill.net>
Date: Sun Aug 5 19:16:26 2018 -0400
remove Chromium from lz4 experiment
commit ee3e201c45afe983508f70713a2d43af74737d8d
Author: Raymond Hill <rhill@raymondhill.net>
Date: Sun Aug 5 18:52:43 2018 -0400
import lz4-block-codec.wasm library
commit 883a3118efcfd749c82356fde7134754d6ae371d
Author: Raymond Hill <rhill@raymondhill.net>
Date: Sun Aug 5 18:50:46 2018 -0400
implement storage compression through lz4-wasm [draft]
commit 48d1ccaba407de447c2cd6747dc3a90839c260a7
Merge: 8ae77e6 b34c897
Author: Raymond Hill <rhill@raymondhill.net>
Date: Sat Aug 4 08:56:51 2018 -0400
Merge branch 'master' of github.com:gorhill/uBlock into lz4
commit 8ae77e6aeeaa85af335e664c2560d2afd37288c6
Author: Raymond Hill <rhill@raymondhill.net>
Date: Wed Jul 25 18:17:45 2018 -0400
experiment with compression
When using paths, platform implementations of setIcon typically
will fetch the resource then convert to image data internally.
It is preferable for uBO to do this conversion itself as it can
be done only once at launch time.
With chromium-based browsers, using image data eliminate the
incessant network traffic to fetch browser icons as reported
in the extension's dev tool, meaning a good chunk of overhead
is eliminated.
Also, use optimal icon sizes, as of now both chromium and firefox
prefers 16px instead of 19px, and 32px instead of 38px.
Upon start-up, uBlock runs all content scripts in manifest.json using
`chrome.tabs.executeScript`. When this API is used, the value of the
last expression is automatically cloned and transferred to the
callback of `chrome.tabs.executeScript`. This is convenient if needed,
and a performance burden otherwise (the latter is the case for uBlock).
There are three content scripts that need to be checked:
- vapi.js
The last expression is often the vAPI object, and it is relatively
expensive to clone this object. This commit sets the value of the
last expression to `void 0` to solve this inefficiency.
- vapi-client.js
No action needed yet; The last expression is `vAPI.shutdown.add(...)`,
which has a void return value.
- contentscript.js
No action needed yet; The last expression is an immediately-invoked
function expression without return value.
* Fix leftovers from old code.
* change changes.procedural.size to changes.procedural.length
changes.procedural is an array so it should be changes.procedural.length
the code works with changes.procedural.size because (undefined !== 0) is always true.
commit ab2b328cf1360a751fa1c58b8521f907eeb1ec50
Author: Raymond Hill <rhill@raymondhill.net>
Date: Thu Apr 12 12:08:30 2018 -0400
fix#3588
commit c4ae7638dfa5a5c7ddec2f9dd2d2988450082542
Author: Raymond Hill <rhill@raymondhill.net>
Date: Thu Apr 12 09:08:56 2018 -0400
detect user stylesheets support from content scripts (#3588)
A new filtering class has been created: "static extended filtering".
This new class is an umbrella class for more specialized filtering
engines:
- Cosmetic filtering
- Scriptlet filtering
- HTML filtering
HTML filtering is available only on platforms which support modifying
the response body on the fly, so only Firefox 57+ at the moment.
With the ability to modify the response body, HTML filtering has
been introduced: removing elements from the DOM before the source
data has been parsed by the browser.
A consequence of HTML filtering ability is to bring back script tag
filtering feature.
* dom-inspector: Improvments
- Fix race between userCSS injection and element highlight resulting in none or not all elements highlighted.
- Fix page being scanned twice resulting in unneeded slowdown.
* dom-inspector: Clear mutationTimer to allow more than one update.
* dom-inspector: Fix procedural filters shown as declarative with expando.
