Adding upstream version 1.55.0+dfsg.upstream/1.55.0+dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1364 insertions, 0 deletions

diff --git a/src/js/contentscript.js b/src/js/contentscript.js
new file mode 100644
index 0000000..8f3a4cf
--- /dev/null
+++ b/src/js/contentscript.js
@@ -0,0 +1,1364 @@
+/*******************************************************************************
+
+    uBlock Origin - a comprehensive, efficient content blocker
+    Copyright (C) 2014-present Raymond Hill
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see {http://www.gnu.org/licenses/}.
+
+    Home: https://github.com/gorhill/uBlock
+*/
+
+'use strict';
+
+/*******************************************************************************
+
+              +--> domCollapser
+              |
+              |
+  domWatcher--+
+              |                  +-- domSurveyor
+              |                  |
+              +--> domFilterer --+-- [domLogger]
+                        |        |
+                        |        +-- [domInspector]
+                        |
+             [domProceduralFilterer]
+
+  domWatcher:
+    Watches for changes in the DOM, and notify the other components about these
+    changes.
+
+  domCollapser:
+    Enforces the collapsing of DOM elements for which a corresponding
+    resource was blocked through network filtering.
+
+  domFilterer:
+    Enforces the filtering of DOM elements, by feeding it cosmetic filters.
+
+  domProceduralFilterer:
+    Enforce the filtering of DOM elements through procedural cosmetic filters.
+    Loaded on demand, only when needed.
+
+  domSurveyor:
+    Surveys the DOM to find new cosmetic filters to apply to the current page.
+
+  domLogger:
+    Surveys the page to find and report the injected cosmetic filters blocking
+    actual elements on the current page. This component is dynamically loaded
+    IF AND ONLY IF uBO's logger is opened.
+
+  If page is whitelisted:
+    - domWatcher: off
+    - domCollapser: off
+    - domFilterer: off
+    - domSurveyor: off
+    - domLogger: off
+
+  I verified that the code in this file is completely flushed out of memory
+  when a page is whitelisted.
+
+  If cosmetic filtering is disabled:
+    - domWatcher: on
+    - domCollapser: on
+    - domFilterer: off
+    - domSurveyor: off
+    - domLogger: off
+
+  If generic cosmetic filtering is disabled:
+    - domWatcher: on
+    - domCollapser: on
+    - domFilterer: on
+    - domSurveyor: off
+    - domLogger: on if uBO logger is opened
+
+  If generic cosmetic filtering is enabled:
+    - domWatcher: on
+    - domCollapser: on
+    - domFilterer: on
+    - domSurveyor: on
+    - domLogger: on if uBO logger is opened
+
+  Additionally, the domSurveyor can turn itself off once it decides that
+  it has become pointless (repeatedly not finding new cosmetic filters).
+
+  The domFilterer makes use of platform-dependent user stylesheets[1].
+
+  [1] "user stylesheets" refer to local CSS rules which have priority over,
+       and can't be overridden by a web page's own CSS rules.
+
+*/
+
+// Abort execution if our global vAPI object does not exist.
+//   https://github.com/chrisaljoudi/uBlock/issues/456
+//   https://github.com/gorhill/uBlock/issues/2029
+
+ // >>>>>>>> start of HUGE-IF-BLOCK
+if ( typeof vAPI === 'object' && !vAPI.contentScript ) {
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.contentScript = true;
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+// https://github.com/uBlockOrigin/uBlock-issues/issues/688#issuecomment-663657508
+{
+    let context = self;
+    try {
+        while (
+            context !== self.top &&
+            context.location.href.startsWith('about:blank') &&
+            context.parent.location.href
+        ) {
+            context = context.parent;
+        }
+    } catch(ex) {
+    }
+    vAPI.effectiveSelf = context;
+}
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.userStylesheet = {
+    added: new Set(),
+    removed: new Set(),
+    apply: function(callback) {
+        if ( this.added.size === 0 && this.removed.size === 0 ) { return; }
+        vAPI.messaging.send('vapi', {
+            what: 'userCSS',
+            add: Array.from(this.added),
+            remove: Array.from(this.removed),
+        }).then(( ) => {
+            if ( callback instanceof Function === false ) { return; }
+            callback();
+        });
+        this.added.clear();
+        this.removed.clear();
+    },
+    add: function(cssText, now) {
+        if ( cssText === '' ) { return; }
+        this.added.add(cssText);
+        if ( now ) { this.apply(); }
+    },
+    remove: function(cssText, now) {
+        if ( cssText === '' ) { return; }
+        this.removed.add(cssText);
+        if ( now ) { this.apply(); }
+    }
+};
+
+/******************************************************************************/
+/******************************************************************************/
+/*******************************************************************************
+
+  The purpose of SafeAnimationFrame is to take advantage of the behavior of
+  window.requestAnimationFrame[1]. If we use an animation frame as a timer,
+  then this timer is described as follow:
+
+  - time events are throttled by the browser when the viewport is not visible --
+    there is no point for uBO to play with the DOM if the document is not
+    visible.
+  - time events are micro tasks[2].
+  - time events are synchronized to monitor refresh, meaning that they can fire
+    at most 1/60 (typically).
+
+  If a delay value is provided, a plain timer is first used. Plain timers are
+  macro-tasks, so this is good when uBO wants to yield to more important tasks
+  on a page. Once the plain timer elapse, an animation frame is used to trigger
+  the next time at which to execute the job.
+
+  [1] https://developer.mozilla.org/en-US/docs/Web/API/window/requestAnimationFrame
+  [2] https://jakearchibald.com/2015/tasks-microtasks-queues-and-schedules/
+
+*/
+
+// https://github.com/gorhill/uBlock/issues/2147
+
+vAPI.SafeAnimationFrame = class {
+    constructor(callback) {
+        this.fid = this.tid = undefined;
+        this.callback = callback;
+    }
+    start(delay) {
+        if ( self.vAPI instanceof Object === false ) { return; }
+        if ( delay === undefined ) {
+            if ( this.fid === undefined ) {
+                this.fid = requestAnimationFrame(( ) => { this.onRAF(); } );
+            }
+            if ( this.tid === undefined ) {
+                this.tid = vAPI.setTimeout(( ) => { this.onSTO(); }, 20000);
+            }
+            return;
+        }
+        if ( this.fid === undefined && this.tid === undefined ) {
+            this.tid = vAPI.setTimeout(( ) => { this.macroToMicro(); }, delay);
+        }
+    }
+    clear() {
+        if ( this.fid !== undefined ) {
+            cancelAnimationFrame(this.fid);
+            this.fid = undefined;
+        }
+        if ( this.tid !== undefined ) {
+            clearTimeout(this.tid);
+            this.tid = undefined;
+        }
+    }
+    macroToMicro() {
+        this.tid = undefined;
+        this.start();
+    }
+    onRAF() {
+        if ( this.tid !== undefined ) {
+            clearTimeout(this.tid);
+            this.tid = undefined;
+        }
+        this.fid = undefined;
+        this.callback();
+    }
+    onSTO() {
+        if ( this.fid !== undefined ) {
+            cancelAnimationFrame(this.fid);
+            this.fid = undefined;
+        }
+        this.tid = undefined;
+        this.callback();
+    }
+};
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+// https://github.com/uBlockOrigin/uBlock-issues/issues/552
+//   Listen and report CSP violations so that blocked resources through CSP
+//   are properly reported in the logger.
+
+{
+    const newEvents = new Set();
+    const allEvents = new Set();
+    let timer;
+
+    const send = function() {
+        if ( self.vAPI instanceof Object === false ) { return; }
+        vAPI.messaging.send('scriptlets', {
+            what: 'securityPolicyViolation',
+            type: 'net',
+            docURL: document.location.href,
+            violations: Array.from(newEvents),
+        }).then(response => {
+            if ( response === true ) { return; }
+            stop();
+        });
+        for ( const event of newEvents ) {
+            allEvents.add(event);
+        }
+        newEvents.clear();
+    };
+
+    const sendAsync = function() {
+        if ( timer !== undefined ) { return; }
+        timer = self.requestIdleCallback(
+            ( ) => { timer = undefined; send(); },
+            { timeout: 2063 }
+        );
+    };
+
+    const listener = function(ev) {
+        if ( ev.isTrusted !== true ) { return; }
+        if ( ev.disposition !== 'enforce' ) { return; }
+        const json = JSON.stringify({
+            url: ev.blockedURL || ev.blockedURI,
+            policy: ev.originalPolicy,
+            directive: ev.effectiveDirective || ev.violatedDirective,
+        });
+        if ( allEvents.has(json) ) { return; }
+        newEvents.add(json);
+        sendAsync();
+    };
+
+    const stop = function() {
+        newEvents.clear();
+        allEvents.clear();
+        if ( timer !== undefined ) {
+            self.cancelIdleCallback(timer);
+            timer = undefined;
+        }
+        document.removeEventListener('securitypolicyviolation', listener);
+        if ( vAPI ) { vAPI.shutdown.remove(stop); }
+    };
+
+    document.addEventListener('securitypolicyviolation', listener);
+    vAPI.shutdown.add(stop);
+
+    // We need to call at least once to find out whether we really need to
+    // listen to CSP violations.
+    sendAsync();
+}
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+// vAPI.domWatcher
+
+{
+    vAPI.domMutationTime = Date.now();
+
+    const addedNodeLists = [];
+    const removedNodeLists = [];
+    const addedNodes = [];
+    const ignoreTags = new Set([ 'br', 'head', 'link', 'meta', 'script', 'style' ]);
+    const listeners = [];
+
+    let domLayoutObserver;
+    let listenerIterator = [];
+    let listenerIteratorDirty = false;
+    let removedNodes = false;
+    let safeObserverHandlerTimer;
+
+    const safeObserverHandler = function() {
+        let i = addedNodeLists.length;
+        while ( i-- ) {
+            const nodeList = addedNodeLists[i];
+            let iNode = nodeList.length;
+            while ( iNode-- ) {
+                const node = nodeList[iNode];
+                if ( node.nodeType !== 1 ) { continue; }
+                if ( ignoreTags.has(node.localName) ) { continue; }
+                if ( node.parentElement === null ) { continue; }
+                addedNodes.push(node);
+            }
+        }
+        addedNodeLists.length = 0;
+        i = removedNodeLists.length;
+        while ( i-- && removedNodes === false ) {
+            const nodeList = removedNodeLists[i];
+            let iNode = nodeList.length;
+            while ( iNode-- ) {
+                if ( nodeList[iNode].nodeType !== 1 ) { continue; }
+                removedNodes = true;
+                break;
+            }
+        }
+        removedNodeLists.length = 0;
+        if ( addedNodes.length === 0 && removedNodes === false ) { return; }
+        for ( const listener of getListenerIterator() ) {
+            try { listener.onDOMChanged(addedNodes, removedNodes); }
+            catch (ex) { }
+        }
+        addedNodes.length = 0;
+        removedNodes = false;
+        vAPI.domMutationTime = Date.now();
+    };
+
+    // https://github.com/chrisaljoudi/uBlock/issues/205
+    //   Do not handle added node directly from within mutation observer.
+    const observerHandler = function(mutations) {
+        let i = mutations.length;
+        while ( i-- ) {
+            const mutation = mutations[i];
+            let nodeList = mutation.addedNodes;
+            if ( nodeList.length !== 0 ) {
+                addedNodeLists.push(nodeList);
+            }
+            nodeList = mutation.removedNodes;
+            if ( nodeList.length !== 0 ) {
+                removedNodeLists.push(nodeList);
+            }
+        }
+        if ( addedNodeLists.length !== 0 || removedNodeLists.length !== 0 ) {
+            safeObserverHandlerTimer.start(
+                addedNodeLists.length < 100 ? 1 : undefined
+            );
+        }
+    };
+
+    const startMutationObserver = function() {
+        if ( domLayoutObserver !== undefined ) { return; }
+        domLayoutObserver = new MutationObserver(observerHandler);
+        domLayoutObserver.observe(document, {
+            //attributeFilter: [ 'class', 'id' ],
+            //attributes: true,
+            childList: true,
+            subtree: true
+        });
+        safeObserverHandlerTimer = new vAPI.SafeAnimationFrame(safeObserverHandler);
+        vAPI.shutdown.add(cleanup);
+    };
+
+    const stopMutationObserver = function() {
+        if ( domLayoutObserver === undefined ) { return; }
+        cleanup();
+        vAPI.shutdown.remove(cleanup);
+    };
+
+    const getListenerIterator = function() {
+        if ( listenerIteratorDirty ) {
+            listenerIterator = listeners.slice();
+            listenerIteratorDirty = false;
+        }
+        return listenerIterator;
+    };
+
+    const addListener = function(listener) {
+        if ( listeners.indexOf(listener) !== -1 ) { return; }
+        listeners.push(listener);
+        listenerIteratorDirty = true;
+        if ( domLayoutObserver === undefined ) { return; }
+        try { listener.onDOMCreated(); }
+        catch (ex) { }
+        startMutationObserver();
+    };
+
+    const removeListener = function(listener) {
+        const pos = listeners.indexOf(listener);
+        if ( pos === -1 ) { return; }
+        listeners.splice(pos, 1);
+        listenerIteratorDirty = true;
+        if ( listeners.length === 0 ) {
+            stopMutationObserver();
+        }
+    };
+
+    const cleanup = function() {
+        if ( domLayoutObserver !== undefined ) {
+            domLayoutObserver.disconnect();
+            domLayoutObserver = undefined;
+        }
+        if ( safeObserverHandlerTimer !== undefined ) {
+            safeObserverHandlerTimer.clear();
+            safeObserverHandlerTimer = undefined;
+        }
+    };
+
+    const start = function() {
+        for ( const listener of getListenerIterator() ) {
+            try { listener.onDOMCreated(); }
+            catch (ex) { }
+        }
+        startMutationObserver();
+    };
+
+    vAPI.domWatcher = { start, addListener, removeListener };
+}
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+vAPI.injectScriptlet = function(doc, text) {
+    if ( !doc ) { return; }
+    let script, url;
+    try {
+        const blob = new self.Blob([ text ], { type: 'text/javascript; charset=utf-8' });
+        url = self.URL.createObjectURL(blob);
+        script = doc.createElement('script');
+        script.async = false;
+        script.src = url;
+        (doc.head || doc.documentElement || doc).appendChild(script);
+    } catch (ex) {
+    }
+    if ( url ) {
+        if ( script ) { script.remove(); }
+        self.URL.revokeObjectURL(url);
+    }
+};
+
+/******************************************************************************/
+/******************************************************************************/
+/*******************************************************************************
+
+  The DOM filterer is the heart of uBO's cosmetic filtering.
+
+  DOMFilterer: adds procedural cosmetic filtering
+
+*/
+
+vAPI.hideStyle = 'display:none!important;';
+
+vAPI.DOMFilterer = class {
+    constructor() {
+        this.commitTimer = new vAPI.SafeAnimationFrame(
+            ( ) => { this.commitNow(); }
+        );
+        this.disabled = false;
+        this.listeners = [];
+        this.stylesheets = [];
+        this.exceptedCSSRules = [];
+        this.exceptions = [];
+        this.convertedProceduralFilters = [];
+        this.proceduralFilterer = null;
+    }
+
+    explodeCSS(css) {
+        const out = [];
+        const cssHide = `{${vAPI.hideStyle}}`;
+        const blocks = css.trim().split(/\n\n+/);
+        for ( const block of blocks ) {
+            if ( block.endsWith(cssHide) === false ) { continue; }
+            out.push(block.slice(0, -cssHide.length).trim());
+        }
+        return out;
+    }
+
+    addCSS(css, details = {}) {
+        if ( typeof css !== 'string' || css.length === 0 ) { return; }
+        if ( this.stylesheets.includes(css) ) { return; }
+        this.stylesheets.push(css);
+        if ( details.mustInject && this.disabled === false ) {
+            vAPI.userStylesheet.add(css);
+        }
+        if ( this.hasListeners() === false ) { return; }
+        if ( details.silent ) { return; }
+        this.triggerListeners({ declarative: this.explodeCSS(css) });
+    }
+
+    exceptCSSRules(exceptions) {
+        if ( exceptions.length === 0 ) { return; }
+        this.exceptedCSSRules.push(...exceptions);
+        if ( this.hasListeners() ) {
+            this.triggerListeners({ exceptions });
+        }
+    }
+
+    addListener(listener) {
+        if ( this.listeners.indexOf(listener) !== -1 ) { return; }
+        this.listeners.push(listener);
+    }
+
+    removeListener(listener) {
+        const pos = this.listeners.indexOf(listener);
+        if ( pos === -1 ) { return; }
+        this.listeners.splice(pos, 1);
+    }
+
+    hasListeners() {
+        return this.listeners.length !== 0;
+    }
+
+    triggerListeners(changes) {
+        for ( const listener of this.listeners ) {
+            listener.onFiltersetChanged(changes);
+        }
+    }
+
+    toggle(state, callback) {
+        if ( state === undefined ) { state = this.disabled; }
+        if ( state !== this.disabled ) { return; }
+        this.disabled = !state;
+        const uss = vAPI.userStylesheet;
+        for ( const css of this.stylesheets ) {
+            if ( this.disabled ) {
+                uss.remove(css);
+            } else {
+                uss.add(css);
+            }
+        }
+        uss.apply(callback);
+    }
+
+    // Here we will deal with:
+    // - Injecting low priority user styles;
+    // - Notifying listeners about changed filterset.
+    // https://www.reddit.com/r/uBlockOrigin/comments/9jj0y1/no_longer_blocking_ads/
+    //   Ensure vAPI is still valid -- it can go away by the time we are
+    //   called, since the port could be force-disconnected from the main
+    //   process. Another approach would be to have vAPI.SafeAnimationFrame
+    //   register a shutdown job: to evaluate. For now I will keep the fix
+    //   trivial.
+    commitNow() {
+        this.commitTimer.clear();
+        if ( vAPI instanceof Object === false ) { return; }
+        vAPI.userStylesheet.apply();
+        if ( this.proceduralFilterer instanceof Object ) {
+            this.proceduralFilterer.commitNow();
+        }
+    }
+
+    commit(commitNow) {
+        if ( commitNow ) {
+            this.commitTimer.clear();
+            this.commitNow();
+        } else {
+            this.commitTimer.start();
+        }
+    }
+
+    proceduralFiltererInstance() {
+        if ( this.proceduralFilterer instanceof Object === false ) {
+            if ( vAPI.DOMProceduralFilterer instanceof Object === false ) {
+                return null;
+            }
+            this.proceduralFilterer = new vAPI.DOMProceduralFilterer(this);
+        }
+        return this.proceduralFilterer;
+    }
+
+    addProceduralSelectors(selectors) {
+        const procedurals = [];
+        for ( const raw of selectors ) {
+            procedurals.push(JSON.parse(raw));
+        }
+        if ( procedurals.length === 0 ) { return; }
+        const pfilterer = this.proceduralFiltererInstance();
+        if ( pfilterer !== null ) {
+            pfilterer.addProceduralSelectors(procedurals);
+        }
+    }
+
+    createProceduralFilter(o) {
+        const pfilterer = this.proceduralFiltererInstance();
+        if ( pfilterer === null ) { return; }
+        return pfilterer.createProceduralFilter(o);
+    }
+
+    getAllSelectors(bits = 0) {
+        const out = {
+            declarative: [],
+            exceptions: this.exceptedCSSRules,
+        };
+        const hasProcedural = this.proceduralFilterer instanceof Object;
+        const includePrivateSelectors = (bits & 0b01) !== 0;
+        const masterToken = hasProcedural
+            ? `[${this.proceduralFilterer.masterToken}]`
+            : undefined;
+        for ( const css of this.stylesheets ) {
+            for ( const block of this.explodeCSS(css) ) {
+                if (
+                    includePrivateSelectors === false &&
+                    masterToken !== undefined &&
+                    block.startsWith(masterToken)
+                ) {
+                    continue;
+                }
+                out.declarative.push(block);
+            }
+        }
+        const excludeProcedurals = (bits & 0b10) !== 0;
+        if ( excludeProcedurals === false ) {
+            out.procedural = [];
+            if ( hasProcedural ) {
+                out.procedural.push(
+                    ...this.proceduralFilterer.selectors.values()
+                );
+            }
+            const proceduralFilterer = this.proceduralFiltererInstance();
+            if ( proceduralFilterer !== null ) {
+                for ( const json of this.convertedProceduralFilters ) {
+                    const pfilter = proceduralFilterer.createProceduralFilter(json);
+                    pfilter.converted = true;
+                    out.procedural.push(pfilter);
+                }
+            }
+        }
+        return out;
+    }
+
+    getAllExceptionSelectors() {
+        return this.exceptions.join(',\n');
+    }
+};
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+// vAPI.domCollapser
+
+{
+    const messaging = vAPI.messaging;
+    const toCollapse = new Map();
+    const src1stProps = {
+        audio: 'currentSrc',
+        embed: 'src',
+        iframe: 'src',
+        img: 'currentSrc',
+        object: 'data',
+        video: 'currentSrc',
+    };
+    const src2ndProps = {
+        audio: 'src',
+        img: 'src',
+        video: 'src',
+    };
+    const tagToTypeMap = {
+        audio: 'media',
+        embed: 'object',
+        iframe: 'sub_frame',
+        img: 'image',
+        object: 'object',
+        video: 'media',
+    };
+    let requestIdGenerator = 1,
+        processTimer,
+        cachedBlockedSet,
+        cachedBlockedSetHash,
+        cachedBlockedSetTimer,
+        toProcess = [],
+        toFilter = [],
+        netSelectorCacheCount = 0;
+
+    const cachedBlockedSetClear = function() {
+        cachedBlockedSet =
+        cachedBlockedSetHash =
+        cachedBlockedSetTimer = undefined;
+    };
+
+    // https://github.com/chrisaljoudi/uBlock/issues/399
+    // https://github.com/gorhill/uBlock/issues/2848
+    //   Use a user stylesheet to collapse placeholders.
+    const getCollapseToken = ( ) => {
+        if ( collapseToken === undefined ) {
+            collapseToken = vAPI.randomToken();
+            vAPI.userStylesheet.add(
+                `[${collapseToken}]\n{display:none!important;}`,
+                true
+            );
+        }
+        return collapseToken;
+    };
+    let collapseToken;
+
+    // https://github.com/chrisaljoudi/uBlock/issues/174
+    //   Do not remove fragment from src URL
+    const onProcessed = function(response) {
+        // This happens if uBO is disabled or restarted.
+        if ( response instanceof Object === false ) {
+            toCollapse.clear();
+            return;
+        }
+
+        const targets = toCollapse.get(response.id);
+        if ( targets === undefined ) { return; }
+
+        toCollapse.delete(response.id);
+        if ( cachedBlockedSetHash !== response.hash ) {
+            cachedBlockedSet = new Set(response.blockedResources);
+            cachedBlockedSetHash = response.hash;
+            if ( cachedBlockedSetTimer !== undefined ) {
+                clearTimeout(cachedBlockedSetTimer);
+            }
+            cachedBlockedSetTimer = vAPI.setTimeout(cachedBlockedSetClear, 30000);
+        }
+        if ( cachedBlockedSet === undefined || cachedBlockedSet.size === 0 ) {
+            return;
+        }
+
+        const selectors = [];
+        let netSelectorCacheCountMax = response.netSelectorCacheCountMax;
+
+        for ( const target of targets ) {
+            const tag = target.localName;
+            let prop = src1stProps[tag];
+            if ( prop === undefined ) { continue; }
+            let src = target[prop];
+            if ( typeof src !== 'string' || src.length === 0 ) {
+                prop = src2ndProps[tag];
+                if ( prop === undefined ) { continue; }
+                src = target[prop];
+                if ( typeof src !== 'string' || src.length === 0 ) { continue; }
+            }
+            if ( cachedBlockedSet.has(tagToTypeMap[tag] + ' ' + src) === false ) {
+                continue;
+            }
+            target.setAttribute(getCollapseToken(), '');
+            // https://github.com/chrisaljoudi/uBlock/issues/1048
+            //   Use attribute to construct CSS rule
+            if ( netSelectorCacheCount > netSelectorCacheCountMax ) { continue; }
+            const value = target.getAttribute(prop);
+            if ( value ) {
+                selectors.push(`${tag}[${prop}="${CSS.escape(value)}"]`);
+                netSelectorCacheCount += 1;
+            }
+        }
+
+        if ( selectors.length === 0 ) { return; }
+        messaging.send('contentscript', {
+            what: 'cosmeticFiltersInjected',
+            type: 'net',
+            hostname: window.location.hostname,
+            selectors,
+        });
+    };
+
+    const send = function() {
+        processTimer = undefined;
+        toCollapse.set(requestIdGenerator, toProcess);
+        messaging.send('contentscript', {
+            what: 'getCollapsibleBlockedRequests',
+            id: requestIdGenerator,
+            frameURL: window.location.href,
+            resources: toFilter,
+            hash: cachedBlockedSetHash,
+        }).then(response => {
+            onProcessed(response);
+        });
+        toProcess = [];
+        toFilter = [];
+        requestIdGenerator += 1;
+    };
+
+    const process = function(delay) {
+        if ( toProcess.length === 0 ) { return; }
+        if ( delay === 0 ) {
+            if ( processTimer !== undefined ) {
+                clearTimeout(processTimer);
+            }
+            send();
+        } else if ( processTimer === undefined ) {
+            processTimer = vAPI.setTimeout(send, delay || 20);
+        }
+    };
+
+    const add = function(target) {
+        toProcess[toProcess.length] = target;
+    };
+
+    const addMany = function(targets) {
+        for ( const target of targets ) {
+            add(target);
+        }
+    };
+
+    const iframeSourceModified = function(mutations) {
+        for ( const mutation of mutations ) {
+            addIFrame(mutation.target, true);
+        }
+        process();
+    };
+    const iframeSourceObserver = new MutationObserver(iframeSourceModified);
+    const iframeSourceObserverOptions = {
+        attributes: true,
+        attributeFilter: [ 'src' ]
+    };
+
+    // https://github.com/gorhill/uBlock/issues/162
+    //   Be prepared to deal with possible change of src attribute.
+    const addIFrame = function(iframe, dontObserve) {
+        if ( dontObserve !== true ) {
+            iframeSourceObserver.observe(iframe, iframeSourceObserverOptions);
+        }
+        const src = iframe.src;
+        if ( typeof src !== 'string' || src === '' ) { return; }
+        if ( src.startsWith('http') === false ) { return; }
+        toFilter.push({ type: 'sub_frame', url: iframe.src });
+        add(iframe);
+    };
+
+    const addIFrames = function(iframes) {
+        for ( const iframe of iframes ) {
+            addIFrame(iframe);
+        }
+    };
+
+    const onResourceFailed = function(ev) {
+        if ( tagToTypeMap[ev.target.localName] !== undefined ) {
+            add(ev.target);
+            process();
+        }
+    };
+
+    const stop = function() {
+        document.removeEventListener('error', onResourceFailed, true);
+        if ( processTimer !== undefined ) {
+            clearTimeout(processTimer);
+        }
+        if ( vAPI.domWatcher instanceof Object ) {
+            vAPI.domWatcher.removeListener(domWatcherInterface);
+        }
+        vAPI.shutdown.remove(stop);
+        vAPI.domCollapser = null;
+    };
+
+    const start = function() {
+        if ( vAPI.domWatcher instanceof Object ) {
+            vAPI.domWatcher.addListener(domWatcherInterface);
+        }
+    };
+
+    const domWatcherInterface = {
+        onDOMCreated: function() {
+            if ( self.vAPI instanceof Object === false ) { return; }
+            if ( vAPI.domCollapser instanceof Object === false ) {
+                if ( vAPI.domWatcher instanceof Object ) {
+                    vAPI.domWatcher.removeListener(domWatcherInterface);
+                }
+                return;
+            }
+            // Listener to collapse blocked resources.
+            // - Future requests not blocked yet
+            // - Elements dynamically added to the page
+            // - Elements which resource URL changes
+            // https://github.com/chrisaljoudi/uBlock/issues/7
+            // Preferring getElementsByTagName over querySelectorAll:
+            //   http://jsperf.com/queryselectorall-vs-getelementsbytagname/145
+            const elems = document.images ||
+                          document.getElementsByTagName('img');
+            for ( const elem of elems ) {
+                if ( elem.complete ) {
+                    add(elem);
+                }
+            }
+            addMany(document.embeds || document.getElementsByTagName('embed'));
+            addMany(document.getElementsByTagName('object'));
+            addIFrames(document.getElementsByTagName('iframe'));
+            process(0);
+
+            document.addEventListener('error', onResourceFailed, true);
+
+            vAPI.shutdown.add(stop);
+        },
+        onDOMChanged: function(addedNodes) {
+            if ( addedNodes.length === 0 ) { return; }
+            for ( const node of addedNodes ) {
+                if ( node.localName === 'iframe' ) {
+                    addIFrame(node);
+                }
+                if ( node.firstElementChild === null ) { continue; }
+                const iframes = node.getElementsByTagName('iframe');
+                if ( iframes.length !== 0 ) {
+                    addIFrames(iframes);
+                }
+            }
+            process();
+        }
+    };
+
+    vAPI.domCollapser = { start };
+}
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+// vAPI.domSurveyor
+
+{
+    // http://www.cse.yorku.ca/~oz/hash.html#djb2
+    //   Must mirror cosmetic filtering compiler's version
+    const hashFromStr = (type, s) => {
+        const len = s.length;
+        const step = len + 7 >>> 3;
+        let hash = (type << 5) + type ^ len;
+        for ( let i = 0; i < len; i += step ) {
+            hash = (hash << 5) + hash ^ s.charCodeAt(i);
+        }
+        return hash & 0xFFFFFF;
+    };
+
+    const addHashes = hashes => {
+        for ( const hash of hashes ) {
+            queriedHashes.add(hash);
+        }
+    };
+
+    const queriedHashes = new Set();
+    const maxSurveyNodes = 65536;
+    const pendingLists = [];
+    const pendingNodes = [];
+    const processedSet = new Set();
+    let domFilterer;
+    let hostname = '';
+    let domChanged = false;
+    let scannedCount = 0;
+    let stopped = false;
+
+    const addPendingList = list => {
+        if ( list.length === 0 ) { return; }
+        pendingLists.push(Array.from(list));
+    };
+
+    const nextPendingNodes = ( ) => {
+        if ( pendingLists.length === 0 ) { return 0; }
+        const bufferSize = 256;
+        let j = 0;
+        do {
+            const nodeList = pendingLists[0];
+            let n = bufferSize - j;
+            if ( n > nodeList.length ) {
+                n = nodeList.length;
+            }
+            for ( let i = 0; i < n; i++ ) {
+                pendingNodes[j+i] = nodeList[i];
+            }
+            j += n;
+            if ( n !== nodeList.length ) {
+                pendingLists[0] = nodeList.slice(n);
+                break;
+            }
+            pendingLists.shift();
+        } while ( j < bufferSize && pendingLists.length !== 0 );
+        return j;
+    };
+
+    const hasPendingNodes = ( ) => {
+        return pendingLists.length !== 0;
+    };
+
+    // Extract all classes/ids: these will be passed to the cosmetic
+    // filtering engine, and in return we will obtain only the relevant
+    // CSS selectors.
+
+    // https://github.com/gorhill/uBlock/issues/672
+    // http://www.w3.org/TR/2014/REC-html5-20141028/infrastructure.html#space-separated-tokens
+    // http://jsperf.com/enumerate-classes/6
+
+    const idFromNode = (node, out) => {
+        const raw = node.id;
+        if ( typeof raw !== 'string' || raw.length === 0 ) { return; }
+        const hash = hashFromStr(0x23 /* '#' */, raw.trim());
+        if ( queriedHashes.has(hash) ) { return; }
+        queriedHashes.add(hash);
+        out.push(hash);
+    };
+
+    // https://github.com/uBlockOrigin/uBlock-issues/discussions/2076
+    //   Performance: avoid using Element.classList
+    const classesFromNode = (node, out) => {
+        const s = node.getAttribute('class');
+        if ( typeof s !== 'string' ) { return; }
+        const len = s.length;
+        for ( let beg = 0, end = 0; beg < len; beg += 1 ) {
+            end = s.indexOf(' ', beg);
+            if ( end === beg ) { continue; }
+            if ( end === -1 ) { end = len; }
+            const hash = hashFromStr(0x2E /* '.' */, s.slice(beg, end));
+            beg = end;
+            if ( queriedHashes.has(hash) ) { continue; }
+            queriedHashes.add(hash);
+            out.push(hash);
+        }
+    };
+
+    const getSurveyResults = (hashes, safeOnly) => {
+        if ( self.vAPI.messaging instanceof Object === false ) {
+            stop(); return;
+        }
+        const promise = hashes.length === 0
+            ? Promise.resolve(null)
+            : self.vAPI.messaging.send('contentscript', {
+                what: 'retrieveGenericCosmeticSelectors',
+                hostname,
+                hashes,
+                exceptions: domFilterer.exceptions,
+                safeOnly,
+            });
+        promise.then(response => {
+            processSurveyResults(response);
+        });
+    };
+
+    const doSurvey = ( ) => {
+        if ( self.vAPI instanceof Object === false ) { return; }
+        const t0 = performance.now();
+        const hashes = [];
+        const nodes = pendingNodes;
+        const deadline = t0 + 4;
+        let processed = 0;
+        let scanned = 0;
+        for (;;) {
+            const n = nextPendingNodes();
+            if ( n === 0 ) { break; }
+            for ( let i = 0; i < n; i++ ) {
+                const node = nodes[i]; nodes[i] = null;
+                if ( domChanged ) {
+                    if ( processedSet.has(node) ) { continue; }
+                    processedSet.add(node);
+                }
+                idFromNode(node, hashes);
+                classesFromNode(node, hashes);
+                scanned += 1;
+            }
+            processed += n;
+            if ( performance.now() >= deadline ) { break; }
+        }
+        //console.info(`[domSurveyor][${hostname}] Surveyed ${scanned}/${processed} nodes in ${(performance.now()-t0).toFixed(2)} ms: ${hashes.length} hashes`);
+        scannedCount += scanned;
+        if ( scannedCount >= maxSurveyNodes ) {
+            stop();
+        }
+        processedSet.clear();
+        getSurveyResults(hashes);
+    };
+
+    const surveyTimer = new vAPI.SafeAnimationFrame(doSurvey);
+
+    // This is to shutdown the surveyor if result of surveying keeps being
+    // fruitless. This is useful on long-lived web page. I arbitrarily
+    // picked 5 minutes before the surveyor is allowed to shutdown. I also
+    // arbitrarily picked 256 misses before the surveyor is allowed to
+    // shutdown.
+    let canShutdownAfter = Date.now() + 300000;
+    let surveyResultMissCount = 0;
+
+    // Handle main process' response.
+
+    const processSurveyResults = response => {
+        if ( stopped ) { return; }
+        const result = response && response.result;
+        let mustCommit = false;
+        if ( result ) {
+            const css = result.injectedCSS;
+            if ( typeof css === 'string' && css.length !== 0 ) {
+                domFilterer.addCSS(css);
+                mustCommit = true;
+            }
+            const selectors = result.excepted;
+            if ( Array.isArray(selectors) && selectors.length !== 0 ) {
+                domFilterer.exceptCSSRules(selectors);
+            }
+        }
+        if ( hasPendingNodes() ) {
+            surveyTimer.start(1);
+        }
+        if ( mustCommit ) {
+            surveyResultMissCount = 0;
+            canShutdownAfter = Date.now() + 300000;
+            return;
+        }
+        surveyResultMissCount += 1;
+        if ( surveyResultMissCount < 256 || Date.now() < canShutdownAfter ) {
+            return;
+        }
+        //console.info(`[domSurveyor][${hostname}] Shutting down, too many misses`);
+        stop();
+        self.vAPI.messaging.send('contentscript', {
+            what: 'disableGenericCosmeticFilteringSurveyor',
+            hostname,
+        });
+    };
+
+    const domWatcherInterface = {
+        onDOMCreated: function() {
+            domFilterer = vAPI.domFilterer;
+            // https://github.com/uBlockOrigin/uBlock-issues/issues/1692
+            //   Look-up safe-only selectors to mitigate probability of
+            //   html/body elements of erroneously being targeted.
+            const hashes = [];
+            if ( document.documentElement !== null ) {
+                idFromNode(document.documentElement, hashes);
+                classesFromNode(document.documentElement, hashes);
+            }
+            if ( document.body !== null ) {
+                idFromNode(document.body, hashes);
+                classesFromNode(document.body, hashes);
+            }
+            if ( hashes.length !== 0 ) {
+                getSurveyResults(hashes, true);
+            }
+            addPendingList(document.querySelectorAll(
+                '[id]:not(html):not(body),[class]:not(html):not(body)'
+            ));
+            if ( hasPendingNodes() ) {
+                surveyTimer.start();
+            }
+        },
+        onDOMChanged: function(addedNodes) {
+            if ( addedNodes.length === 0 ) { return; }
+            domChanged = true;
+            for ( const node of addedNodes ) {
+                addPendingList([ node ]);
+                if ( node.firstElementChild === null ) { continue; }
+                addPendingList(
+                    node.querySelectorAll(
+                        '[id]:not(html):not(body),[class]:not(html):not(body)'
+                    )
+                );
+            }
+            if ( hasPendingNodes() ) {
+                surveyTimer.start(1);
+            }
+        }
+    };
+
+    const start = details => {
+        if ( self.vAPI instanceof Object === false ) { return; }
+        if ( self.vAPI.domFilterer instanceof Object === false ) { return; }
+        if ( self.vAPI.domWatcher instanceof Object === false ) { return; }
+        hostname = details.hostname;
+        self.vAPI.domWatcher.addListener(domWatcherInterface);
+    };
+
+    const stop = ( ) => {
+        stopped = true;
+        pendingLists.length = 0;
+        surveyTimer.clear();
+        if ( self.vAPI instanceof Object === false ) { return; }
+        if ( self.vAPI.domWatcher instanceof Object ) {
+            self.vAPI.domWatcher.removeListener(domWatcherInterface);
+        }
+        self.vAPI.domSurveyor = null;
+    };
+
+    self.vAPI.domSurveyor = { start, addHashes };
+}
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+// vAPI.bootstrap:
+//   Bootstrapping allows all components of the content script
+//   to be launched if/when needed.
+
+{
+    const onDomReady = ( ) => {
+        // This can happen on Firefox. For instance:
+        // https://github.com/gorhill/uBlock/issues/1893
+        if ( window.location === null ) { return; }
+        if ( self.vAPI instanceof Object === false ) { return; }
+
+        vAPI.messaging.send('contentscript', {
+            what: 'shouldRenderNoscriptTags',
+        });
+
+        if ( vAPI.domFilterer instanceof Object ) {
+            vAPI.domFilterer.commitNow();
+        }
+
+        if ( vAPI.domWatcher instanceof Object ) {
+            vAPI.domWatcher.start();
+        }
+
+        // Element picker works only in top window for now.
+        if (
+            window !== window.top ||
+            vAPI.domFilterer instanceof Object === false
+        ) {
+            return;
+        }
+
+        // To be used by element picker/zapper.
+        vAPI.mouseClick = { x: -1, y: -1 };
+
+        const onMouseClick = function(ev) {
+            if ( ev.isTrusted === false ) { return; }
+            vAPI.mouseClick.x = ev.clientX;
+            vAPI.mouseClick.y = ev.clientY;
+
+            // https://github.com/chrisaljoudi/uBlock/issues/1143
+            //   Find a link under the mouse, to try to avoid confusing new tabs
+            //   as nuisance popups.
+            // https://github.com/uBlockOrigin/uBlock-issues/issues/777
+            //   Mind that href may not be a string.
+            const elem = ev.target.closest('a[href]');
+            if ( elem === null || typeof elem.href !== 'string' ) { return; }
+            vAPI.messaging.send('contentscript', {
+                what: 'maybeGoodPopup',
+                url: elem.href || '',
+            });
+        };
+
+        document.addEventListener('mousedown', onMouseClick, true);
+
+        // https://github.com/gorhill/uMatrix/issues/144
+        vAPI.shutdown.add(function() {
+            document.removeEventListener('mousedown', onMouseClick, true);
+        });
+    };
+
+    // https://github.com/uBlockOrigin/uBlock-issues/issues/403
+    //   If there was a spurious port disconnection -- in which case the
+    //   response is expressly set to `null`, rather than undefined or
+    //   an object -- let's stay around, we may be given the opportunity
+    //   to try bootstrapping again later.
+
+    const onResponseReady = response => {
+        if ( response instanceof Object === false ) { return; }
+        vAPI.bootstrap = undefined;
+
+        // cosmetic filtering engine aka 'cfe'
+        const cfeDetails = response && response.specificCosmeticFilters;
+        if ( !cfeDetails || !cfeDetails.ready ) {
+            vAPI.domWatcher = vAPI.domCollapser = vAPI.domFilterer =
+            vAPI.domSurveyor = vAPI.domIsLoaded = null;
+            return;
+        }
+
+        vAPI.domCollapser.start();
+
+        const {
+            noSpecificCosmeticFiltering,
+            noGenericCosmeticFiltering,
+            scriptletDetails,
+        } = response;
+
+        vAPI.noSpecificCosmeticFiltering = noSpecificCosmeticFiltering;
+        vAPI.noGenericCosmeticFiltering = noGenericCosmeticFiltering;
+
+        if ( noSpecificCosmeticFiltering && noGenericCosmeticFiltering ) {
+            vAPI.domFilterer = null;
+            vAPI.domSurveyor = null;
+        } else {
+            const domFilterer = vAPI.domFilterer = new vAPI.DOMFilterer();
+            if ( noGenericCosmeticFiltering || cfeDetails.disableSurveyor ) {
+                vAPI.domSurveyor = null;
+            }
+            domFilterer.exceptions = cfeDetails.exceptionFilters;
+            domFilterer.addCSS(cfeDetails.injectedCSS);
+            domFilterer.addProceduralSelectors(cfeDetails.proceduralFilters);
+            domFilterer.exceptCSSRules(cfeDetails.exceptedFilters);
+            domFilterer.convertedProceduralFilters = cfeDetails.convertedProceduralFilters;
+            vAPI.userStylesheet.apply();
+        }
+
+        if ( scriptletDetails && typeof self.uBO_scriptletsInjected !== 'string' ) {
+            self.uBO_scriptletsInjected = scriptletDetails.filters;
+            if ( scriptletDetails.mainWorld ) {
+                vAPI.injectScriptlet(document, scriptletDetails.mainWorld);
+                vAPI.injectedScripts = scriptletDetails.mainWorld;
+            }
+        }
+
+        if ( vAPI.domSurveyor ) {
+            if ( Array.isArray(cfeDetails.genericCosmeticHashes) ) {
+                vAPI.domSurveyor.addHashes(cfeDetails.genericCosmeticHashes);
+            }
+            vAPI.domSurveyor.start(cfeDetails);
+        }
+
+        const readyState = document.readyState;
+        if ( readyState === 'interactive' || readyState === 'complete' ) {
+            return onDomReady();
+        }
+        document.addEventListener('DOMContentLoaded', onDomReady, { once: true });
+    };
+
+    vAPI.bootstrap = function() {
+        vAPI.messaging.send('contentscript', {
+            what: 'retrieveContentScriptParameters',
+            url: vAPI.effectiveSelf.location.href,
+            needScriptlets: typeof self.uBO_scriptletsInjected !== 'string',
+        }).then(response => {
+            onResponseReady(response);
+        });
+    };
+}
+
+// This starts bootstrap process.
+vAPI.bootstrap();
+
+/******************************************************************************/
+/******************************************************************************/
+/******************************************************************************/
+
+}
+// <<<<<<<< end of HUGE-IF-BLOCK