Documentation / Configuration
Configuration
Configuration
Browsertime is highly configurable, let’s check it out!
The options #
You have the following options when running Browsertime within docker (run docker run sitespeedio/browsertime --help to get the list on your command line):
browsertime.js [options] <url>/<scriptFile>
timeouts
--timeouts.browserStart Timeout when waiting for browser to start, in milliseconds [number] [default: 60000]
--timeouts.pageLoad Timeout when waiting for url to load, in milliseconds [number] [default: 300000]
--timeouts.script Timeout when running browser scripts, in milliseconds [number] [default: 120000]
--timeouts.pageCompleteCheck, --maxLoadTime Timeout when waiting for page to complete loading, in milliseconds [number] [default: 120000]
--timeouts.networkIdle Timeout when running pageCompleteCheckNetworkIdle, in milliseconds [number] [default: 5000]
chrome
--chrome.args Extra command line arguments to pass to the Chrome process (e.g. --no-sandbox). To add multiple arguments to Chrome, repeat --chrome.args once per argument.
--chrome.binaryPath Path to custom Chrome binary (e.g. Chrome Canary). On OS X, the path should be to the binary inside the app bundle, e.g. "/Applications/Google Chrome Canary.app/Contents/MacOS/Google Chrome Canary"
--chrome.chromedriverPath Path to custom ChromeDriver binary. Make sure to use a ChromeDriver version that's compatible with the version of Chrome you're using
--chrome.chromedriverPort Specify "--port" args for chromedriver prcocess [number]
--chrome.mobileEmulation.deviceName Name of device to emulate. Works only standalone (see list in Chrome DevTools, but add phone like 'iPhone 6'). This will override your userAgent string.
--chrome.mobileEmulation.width Width in pixels of emulated mobile screen (e.g. 360) [number]
--chrome.mobileEmulation.height Height in pixels of emulated mobile screen (e.g. 640) [number]
--chrome.mobileEmulation.pixelRatio Pixel ratio of emulated mobile screen (e.g. 2.0)
--chrome.android.package Run Chrome on your Android device. Set to com.android.chrome for default Chrome version. You need to have adb installed to make this work.
--chrome.android.activity Name of the Activity hosting the WebView.
--chrome.android.process Process name of the Activity hosting the WebView. If not given, the process name is assumed to be the same as chrome.android.package.
--chrome.android.deviceSerial Choose which device to use. If you do not set it, first device will be used.
--chrome.traceCategories A comma separated list of Tracing event categories to include in the Trace log. Default no trace categories is collected. [string]
--chrome.traceCategory Add a trace category to the default ones. Use --chrome.traceCategory multiple times if you want to add multiple categories. Example: --chrome.traceCategory disabled-by-default-v8.cpu_profiler [string]
--chrome.enableTraceScreenshots, --enableTraceScreenshots Include screenshots in the trace log (enabling the trace category disabled-by-default-devtools.screenshot). [boolean]
--chrome.enableChromeDriverLog Log Chromedriver communication to a log file. [boolean]
--chrome.enableVerboseChromeDriverLog Log verboose Chromedriver communication to a log file. [boolean]
--chrome.timeline, --chrome.trace Collect the timeline data. Drag and drop the JSON in your Chrome detvools timeline panel or check out the CPU metrics in the Browsertime.json [boolean]
--chrome.timelineRecordingType, --chrome.traceRecordingType Expose the start/stop commands for the chrome trace [string] [choices: "pageload", "custom"] [default: "pageload"]
--chrome.collectPerfLog Collect performance log from Chrome with Page and Network events and save to disk. [boolean]
--chrome.collectNetLog Collect network log from Chrome and save to disk. [boolean]
--chrome.netLogCaptureMode Choose capture mode for Chromes netlog. [choices: "Default", "IncludeSensitive", "Everything"] [default: "IncludeSensitive"]
--chrome.collectConsoleLog Collect Chromes console log and save to disk. [boolean]
--chrome.appendToUserAgent Append to the user agent. [string]
--chrome.noDefaultOptions Prevent Browsertime from setting its default options for Chrome [boolean]
--chrome.cleanUserDataDir If you use --user-data-dir as an argument to Chrome and want to clean that directory between each iteration you should use --chrome.cleanUserDataDir true. [boolean]
--chrome.CPUThrottlingRate Enables CPU throttling to emulate slow CPUs. Throttling rate as a slowdown factor (1 is no throttle, 2 is 2x slowdown, etc) [number]
--chrome.includeResponseBodies Include response bodies in the HAR file. [choices: "none", "all", "html"] [default: "none"]
--chrome.cdp.performance Collect Chrome perfromance metrics from Chrome DevTools Protocol [boolean] [default: true]
--chrome.blockDomainsExcept, --blockDomainsExcept Block all domains except this domain. Use it multiple time to keep multiple domains. You can also wildcard domains like *.sitespeed.io. Use this when you wanna block out all third parties.
--chrome.ignoreCertificateErrors Make Chrome ignore certificate errors. Defaults to true. [boolean] [default: true]
android
--android.powerTesting, --androidPower Enables android power testing - charging must be disabled for this.(You have to disable charging yourself for this - it depends on the phone model). [boolean]
--android.ignoreShutdownFailures, --ignoreShutdownFailures If set, shutdown failures will be ignored on Android. [boolean] [default: false]
--android.rooted, --androidRooted If your phone is rooted you can use this to set it up following Mozillas best practice for stable metrics. [boolean] [default: false]
--android.pinCPUSpeed, --androidPinCPUSpeed Using a Samsung A51 or Moto G5 you can choose how to pin the CPU to better align the speed with your users. This only works on rooted phones and together with --android.rooted [choices: "min", "middle", "max"] [default: "min"]
--android.batteryTemperatureLimit, --androidBatteryTemperatureLimit Do the battery temperature need to be below a specific limit before we start the test?
--android.batteryTemperatureWaitTimeInSeconds, --androidBatteryTemperatureWaitTimeInSeconds How long time to wait (in seconds) if the androidBatteryTemperatureWaitTimeInSeconds is not met before the next try [default: 120]
--android.batteryTemperatureReboot, --androidBatteryTemperatureReboot If your phone does not get the minimum temperature aftet the wait time, reboot the phone. [boolean] [default: false]
--android.pretestPowerPress, --androidPretestPowerPress Press the power button on the phone before a test starts. [boolean] [default: false]
--android.pretestPressHomeButton, --androidPretestPressHomeButton Press the home button on the phone before a test starts. [boolean] [default: false]
--android.verifyNetwork, --androidVerifyNetwork Before a test start, verify that the device has a Internet connection by pinging 8.8.8.8 (or a configurable domain with --androidPingAddress) [boolean] [default: false]
--android.gnirehtet, --gnirehtet Start gnirehtet and reverse tethering the traffic from your Android phone. [boolean] [default: false]
firefox
--firefox.binaryPath Path to custom Firefox binary (e.g. Firefox Nightly). On OS X, the path should be to the binary inside the app bundle, e.g. /Applications/Firefox.app/Contents/MacOS/firefox-bin
--firefox.geckodriverPath Path to custom geckodriver binary. Make sure to use a geckodriver version that's compatible with the version of Firefox (Gecko) you're using
--firefox.geckodriverArgs Flags passed in to Geckodriver see https://firefox-source-docs.mozilla.org/testing/geckodriver/Flags.html. Use it like --firefox.geckodriverArgs="--marionette-port" --firefox.geckodriverArgs=1027 [string]
--firefox.appendToUserAgent Append to the user agent. [string]
--firefox.nightly Use Firefox Nightly. Works on OS X. For Linux you need to set the binary path. [boolean]
--firefox.beta Use Firefox Beta. Works on OS X. For Linux you need to set the binary path. [boolean]
--firefox.developer Use Firefox Developer. Works on OS X. For Linux you need to set the binary path. [boolean]
--firefox.preference Extra command line arguments to pass Firefox preferences by the format key:value To add multiple preferences, repeat --firefox.preference once per argument.
--firefox.args Extra command line arguments to pass to the Firefox process (e.g. --MOZ_LOG). To add multiple arguments to Firefox, repeat --firefox.args once per argument.
--firefox.includeResponseBodies Include response bodies in HAR [choices: "none", "all", "html"] [default: "none"]
--firefox.appconstants Include Firefox AppConstants information in the results [boolean] [default: false]
--firefox.acceptInsecureCerts Accept insecure certs [boolean]
--firefox.bidihar Use the new bidi HAR generator [boolean] [default: false]
--firefox.windowRecorder Use the internal compositor-based Firefox window recorder to emit PNG files for each frame that is a meaningful change. The PNG output will further be merged into a variable frame rate video for analysis. Use this instead of ffmpeg to record a video (you still need the --video flag). [boolean] [default: false]
--firefox.memoryReport Measure firefox resident memory after each iteration. [boolean] [default: false]
--firefox.memoryReportParams.minizeFirst Force a collection before dumping and measuring the memory report. [boolean] [default: false]
--firefox.geckoProfiler Collect a profile using the internal gecko profiler [boolean] [default: false]
--firefox.geckoProfilerRecordingType Expose the start/stop commands for the gecko profiler [string] [choices: "pageload", "custom"] [default: "pageload"]
--firefox.geckoProfilerParams.features Enabled features during gecko profiling [string] [default: "js,stackwalk,leaf"]
--firefox.geckoProfilerParams.threads Threads to profile. [string] [default: "GeckoMain,Compositor,Renderer"]
--firefox.geckoProfilerParams.interval Sampling interval in ms. Defaults to 1 on desktop, and 4 on android. [number]
--firefox.geckoProfilerParams.bufferSize Buffer size in elements. Default is ~90MB. [number] [default: 13107200]
--firefox.perfStats Collect gecko performance statistics as measured internally by the firefox browser. See https://searchfox.org/mozilla-central/source/tools/performance/PerfStats.h#24-33 [boolean] [default: false]
--firefox.perfStatsParams.mask Mask to decide which features to enable [number] [default: 4294967295]
--firefox.collectMozLog Collect the MOZ HTTP log (by default). See --firefox.setMozLog if you need to specify the logs you wish to gather. [boolean]
--firefox.powerConsumption Enable power consumption collection (in Wh). To get the consumption you also need to set firefox.geckoProfilerParams.features to include power. [boolean] [default: false]
--firefox.setMozLog Use in conjunction with firefox.collectMozLog to set MOZ_LOG to something specific. Without this, the HTTP logs will be collected by default [default: "timestamp,nsHttp:5,cache2:5,nsSocketTransport:5,nsHostResolver:5"]
--firefox.disableBrowsertimeExtension Disable installing the browsertime extension. [boolean]
--firefox.noDefaultPrefs Prevents browsertime from setting its default preferences. [boolean] [default: false]
--firefox.disableSafeBrowsing Disable safebrowsing. [boolean] [default: true]
--firefox.disableTrackingProtection Disable Tracking Protection. [boolean] [default: true]
--firefox.android.package Run Firefox or a GeckoView-consuming App on your Android device. Set to org.mozilla.geckoview_example for default Firefox version. You need to have adb installed to make this work.
--firefox.android.activity Name of the Activity hosting the GeckoView.
--firefox.android.deviceSerial Choose which device to use. If you do not set it, first device will be used.
--firefox.android.intentArgument Configure how the Android intent is launched. Passed through to `adb shell am start ...`; follow the format at https://developer.android.com/studio/command-line/adb#IntentSpec. To add multiple arguments, repeat --firefox.android.intentArgument once per argument.
--firefox.profileTemplate Profile template directory that will be cloned and used as the base of each profile each instance of Firefox is launched against. Use this to pre-populate databases with certificates, tracking protection lists, etc.
selenium
--selenium.url URL to a running Selenium server (e.g. to run a browser on another machine).
video
--videoParams.framerate Frames per second [default: 30]
--videoParams.crf Constant rate factor see https://trac.ffmpeg.org/wiki/Encode/H.264#crf [default: 23]
--videoParams.addTimer Add timer and metrics to the video. [boolean] [default: true]
--videoParams.debug Turn on debug to record a video with all pre/post and scripts/URLS you test in one iteration. Visual Metrics will then automatically be disabled. [boolean] [default: false]
--videoParams.keepOriginalVideo Keep the original video. Use it when you have a Visual Metrics bug and want to create an issue at GitHub [boolean] [default: false]
--videoParams.thumbsize The maximum size of the thumbnail in the filmstrip. Default is 400 pixels in either direction. If videoParams.filmstripFullSize is used that setting overrides this. [default: 400]
--videoParams.filmstripFullSize Keep original sized screenshots. Will make the run take longer time [boolean] [default: false]
--videoParams.filmstripQuality The quality of the filmstrip screenshots. 0-100. [default: 75]
--videoParams.createFilmstrip Create filmstrip screenshots. [boolean] [default: true]
--videoParams.nice Use nice when running FFMPEG during the run. A value from -20 to 19 https://linux.die.net/man/1/nice [default: 0]
--videoParams.taskset Start FFMPEG with taskset -c <CPUS> to pin FFMPG to specific CPU(s). Specify a numerical list of processors. The list may contain multiple items, separated by comma, and ranges. For example, "0,5,7,9-11".
--videoParams.convert Convert the original video to a viewable format (for most video players). Turn that off to make a faster run. [boolean] [default: true]
--videoParams.threads Number of threads to use for video recording. Default is determined by ffmpeg. [default: 0]
edge
--edge.edgedriverPath Path to custom msedgedriver version (need to match your Egde version).
--edge.binaryPath Path to custom Edge binary
safari
--safari.ios Use Safari on iOS. You need to choose browser Safari and iOS to run on iOS. [boolean] [default: false]
--safari.deviceName Set the device name. Device names for connected devices are shown in iTunes.
--safari.deviceUDID Set the device UDID. If Xcode is installed, UDIDs for connected devices are available via the output of "xcrun simctl list devices" and in the Device and Simulators window (accessed in Xcode via "Window > Devices and Simulators")
--safari.deviceType Set the device type. If the value of safari:deviceType is `iPhone`, safaridriver will only create a session using an iPhone device or iPhone simulator. If the value of safari:deviceType is `iPad`, safaridriver will only create a session using an iPad device or iPad simulator.
--safari.useTechnologyPreview Use Safari Technology Preview [boolean] [default: false]
--safari.diagnose When filing a bug report against safaridriver, it is highly recommended that you capture and include diagnostics generated by safaridriver. Diagnostic files are saved to ~/Library/Logs/com.apple.WebDriver/
--safari.useSimulator If the value of useSimulator is true, safaridriver will only use iOS Simulator hosts. If the value of safari:useSimulator is false, safaridriver will not use iOS Simulator hosts. NOTE: An Xcode installation is required in order to run WebDriver tests on iOS Simulator hosts. [boolean] [default: false]
Screenshot
--screenshot Save one screenshot per iteration. [boolean] [default: false]
--screenshotLCP Save one screenshot per iteration that shows the largest contentful paint element (if the browser supports LCP). [boolean] [default: false]
--screenshotLS Save one screenshot per iteration that shows the layout shift elements (if the browser supports layout shift). [boolean] [default: false]
--screenshotParams.type Set the file type of the screenshot [choices: "png", "jpg"] [default: "jpg"]
--screenshotParams.png.compressionLevel zlib compression level [default: 6]
--screenshotParams.jpg.quality Quality of the JPEG screenshot. 1-100 [default: 80]
--screenshotParams.maxSize The max size of the screenshot (width and height). [default: 2000]
PageLoad
--pageCompleteCheck Supply a JavaScript (inline or JavaScript file) that decides when the browser is finished loading the page and can start to collect metrics. The JavaScript snippet is repeatedly queried to see if page has completed loading (indicated by the script returning true). Use it to fetch timings happening after the loadEventEnd. By default the tests ends 2 seconds after loadEventEnd. Also checkout --pageCompleteCheckInactivity and --pageCompleteCheckPollTimeout
--pageCompleteWaitTime How long time you want to wait for your pageComplteteCheck to finish, after it is signaled to closed. Extra parameter passed on to your pageCompleteCheck. [default: 8000]
--pageCompleteCheckInactivity Alternative way to choose when to end your test. This will wait for 2 seconds of inactivity that happens after loadEventEnd. [boolean] [default: false]
--pageCompleteCheckNetworkIdle Alternative way to choose when to end your test that works in Chrome and Firefox. Uses CDP or WebDriver Bidi to look at network traffic instead of running JavaScript in the browser to know when to end the test. By default this will wait 5 seconds of inactivity in the network log (no requets/responses in 5 seconds). Use --timeouts.networkIdle to change the 5 seconds. The test will end after 2 minutes if there is still activity on the network. You can change that timout using --timeouts.pageCompleteCheck [boolean] [default: false]
--pageCompleteCheckPollTimeout The time in ms to wait for running the page complete check the next time. [number] [default: 1500]
--pageCompleteCheckStartWait The time in ms to wait for running the page complete check for the first time. Use this when you have a pageLoadStrategy set to none [number] [default: 5000]
--pageLoadStrategy Set the strategy to waiting for document readiness after a navigation event. After the strategy is ready, your pageCompleteCheck will start running. [string] [choices: "eager", "none", "normal"] [default: "none"]
--timeToSettle Extra time added for the browser to settle before starting to test a URL. This delay happens after the browser was opened and before the navigation to the URL [number] [default: 0]
--webdriverPageload Use webdriver.get to initialize the page load instead of window.location. [boolean] [default: false]
--cacheClearRaw Use internal browser functionality to clear browser cache between runs instead of only using Selenium. [boolean] [default: false]
--flushDNS Flush DNS between runs, works on Mac OS and Linux. Your user needs sudo rights to be able to flush the DNS. [boolean] [default: false]
--spa Convenient parameter to use if you test a SPA application: will automatically wait for X seconds after last network activity and use hash in file names. Read more: https://www.sitespeed.io/documentation/sitespeed.io/spa/ [boolean] [default: false]
--browserRestartTries If the browser fails to start, you can retry to start it this amount of times. [number] [default: 3]
proxy
--proxy.pac Proxy auto-configuration (URL) [string]
--proxy.ftp Ftp proxy (host:port) [string]
--proxy.http Http proxy (host:port) [string]
--proxy.https Https proxy (host:port) [string]
--proxy.bypass Comma separated list of hosts to connect to directly, bypassing other proxies for that host [string]
connectivity
-c, --connectivity.profile The connectivity profile. [choices: "4g", "3g", "3gfast", "3gslow", "3gem", "2g", "cable", "native", "custom"] [default: "native"]
--connectivity.down, --connectivity.downstreamKbps This option requires --connectivity.profile be set to "custom".
--connectivity.up, --connectivity.upstreamKbps This option requires --connectivity.profile be set to "custom".
--connectivity.rtt, --connectivity.latency This option requires --connectivity.profile be set to "custom".
--connectivity.variance This option requires --connectivity.engine be set to "throttle". It will add a variance to the rtt between each run. --connectivity.variance 2 means it will run with a random variance of max 2% between runs.
--connectivity.alias Give your connectivity profile a custom name
--connectivity.engine The engine for connectivity. Throttle works on Mac and tc based Linux. For mobile you can use Humble if you have a Humble setup. Use external if you set the connectivity outside of Browsertime. The best way do to this is described in https://github.com/sitespeedio/browsertime#connectivity. [choices: "external", "throttle", "humble"] [default: "external"]
--connectivity.throttle.localhost Add latency/delay on localhost. Perfect for testing with WebPageReplay [boolean] [default: false]
--connectivity.humble.url The path to your Humble instance. For example http://raspberrypi:3000 [string]
debug
--debug Run Browsertime in debug mode. [boolean] [default: false]
Options:
--cpu Easy way to enable both chrome.timeline for Chrome and geckoProfile for Firefox [boolean]
--enableProfileRun Make one extra run that collects the profiling trace log (no other metrics is collected). For Chrome it will collect the timeline trace, for Firefox it will get the Geckoprofiler trace. This means you do not need to get the trace for all runs and can skip the overhead it produces. [boolean]
--video Record a video and store the video. Set it to false to remove the video that is created by turning on visualMetrics. To remove fully turn off video recordings, make sure to set video and visualMetrics to false. Requires FFMpeg to be installed. [boolean]
--visualMetrics Collect Visual Metrics like First Visual Change, SpeedIndex, Perceptual Speed Index and Last Visual Change. Requires FFMpeg and Python dependencies [boolean]
--visualElements, --visuaElements Collect Visual Metrics from elements. Works only with --visualMetrics turned on. By default you will get visual metrics from the largest image within the view port and the largest h1. You can also configure to pickup your own defined elements with --scriptInput.visualElements [boolean]
--visualMetricsPerceptual Collect Perceptual Speed Index when you run --visualMetrics. [boolean]
--visualMetricsContentful Collect Contentful Speed Index when you run --visualMetrics. [boolean]
--visualMetricsPortable Use the portable visual-metrics processing script (no ImageMagick dependencies). [boolean] [default: true]
--scriptInput.visualElements Include specific elements in visual elements. Give the element a name and select it with document.body.querySelector. Use like this: --scriptInput.visualElements name:domSelector see https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors. Add multiple instances to measure multiple elements. Visual Metrics will use these elements and calculate when they are visible and fully rendered.
--scriptInput.longTask, --minLongTaskLength Set the minimum length of a task to be categorised as a CPU Long Task. It can never be smaller than 50. The value is in ms and only works in Chromium browsers at the moment. [number] [default: 50]
-b, --browser Specify browser. Safari only works on OS X/iOS. Edge only work on OS that supports Edge. [choices: "chrome", "firefox", "edge", "safari"] [default: "chrome"]
--android Short key to use Android. Defaults to use com.android.chrome unless --browser is specified. [boolean] [default: false]
--processStartTime Capture browser process start time (in milliseconds). Android only for now. [boolean] [default: false]
-n, --iterations Number of times to test the url (restarting the browser between each test) [number] [default: 3]
--prettyPrint Enable to print json/har with spaces and indentation. Larger files, but easier on the eye. [boolean] [default: false]
--delay Delay between runs, in milliseconds [number] [default: 0]
-r, --requestheader Request header that will be added to the request. Add multiple instances to add multiple request headers. Works for Firefox and Chrome. Use the following format key:value
--cookie Cookie that will be added to the request. Add multiple instances to add multiple request cookies. Works for Firefox and Chrome. Use the following format cookieName=cookieValue
--injectJs Inject JavaScript into the current page at document_start. Works for Firefox, Chrome and Edge. When injecting to Firefox make sure to wrap the code in a function!
--block Domain to block or URL or URL pattern to block. If you use Chrome you can also use --blockDomainsExcept (that is more performant). Works in Chrome/Edge. For Firefox you block a URL if you start with http else you will block by setting a domain, like upload.wikimedia.org
--percentiles The percentile values within the data browsertime will calculate and report. This argument uses Yargs arrays and you you to set them correctly it is recommended to use a configuraration file instead. [array] [default: [0,10,90,99,100]]
--decimals The decimal points browsertime statistics round to. [number] [default: 0]
--iqr Use IQR, or Inter Quartile Range filtering filters data based on the spread of the data. See https://en.wikipedia.org/wiki/Interquartile_range. In some cases, IQR filtering may not filter out anything. This can happen if the acceptable range is wider than the bounds of your dataset. [boolean] [default: false]
--basicAuth Use it if your server is behind Basic Auth. Format: username@password (Only Chrome and Firefox at the moment).
--preScript, --setUp Selenium script(s) to run before you test your URL/script. They will run outside of the analyse phase. Note that --preScript can be passed multiple times.
--postScript, --tearDown Selenium script(s) to run after you test your URL. They will run outside of the analyse phase. Note that --postScript can be passed multiple times.
--script Add custom Javascript to run after the page has finished loading to collect metrics. If a single js file is specified, it will be included in the category named "custom" in the output json. Pass a folder to include all .js scripts in the folder, and have the folder name be the category. Note that --script can be passed multiple times.
--userAgent Override user agent
--appendToUserAgent Append a String to the user agent. Works in Chrome/Edge and Firefox.
-q, --silent Only output info in the logs, not to the console. Enter twice to suppress summary line. [count]
-o, --output Specify file name for Browsertime data (ex: 'browsertime'). Unless specified, file will be named browsertime.json
--har Specify file name for .har file (ex: 'browsertime'). Unless specified, file will be named browsertime.har
--skipHar Pass --skipHar to not collect a HAR file. [boolean]
--gzipHar Pass --gzipHar to gzip the HAR file [boolean]
--config Path to JSON config file. You can also use a .browsertime.json file that will automatically be found by Browsertime using find-up.
--viewPort Size of browser window WIDTHxHEIGHT or "maximize". Note that "maximize" is ignored for xvfb.
--resultDir Set result directory for the files produced by Browsertime
--useSameDir Store all files in the same structure and do not use the path structure released in 4.0. Use this only if you are testing ONE URL.
--xvfb Start xvfb before the browser is started [boolean] [default: false]
--xvfbParams.display The display used for xvfb [default: 99]
--tcpdump Collect a tcpdump for each tested URL. [boolean] [default: false]
--tcpdumpPacketBuffered Use together with --tcpdump to save each packet directly to the file, instead of buffering. [boolean] [default: false]
--urlAlias Use an alias for the URL. You need to pass on the same amount of alias as URLs. The alias is used as the name of the URL and used for filepath. Pass on multiple --urlAlias for multiple alias/URLs. You can also add alias direct in your script. [string]
--preURL, --warmLoad A URL that will be accessed first by the browser before the URL that you wanna analyze. Use it to fill the browser cache.
--preURLDelay, --warmLoadDealy Delay between preURL and the URL you want to test (in milliseconds) [default: 1500]
--userTimingAllowList All userTimings are captured by default this option takes a regex that will allow which userTimings to capture in the results.
--headless Run the browser in headless mode. Works for Firefox and Chrome. [boolean] [default: false]
--extension Path to a WebExtension to be installed in the browser. Note that --extension can be passed multiple times.
--cjs Load scripting files that ends with .js as common js. Default (false) loads files as esmodules. [boolean] [default: false]
--preWarmServer Do pre test requests to the URL(s) that you want to test that is not measured. Do that to make sure your web server is ready to serve. The pre test requests is done with another browser instance that is closed after pre testing is done. [boolean] [default: false]
--preWarmServerWaitTime The wait time before you start the real testing after your pre-cache request. [number] [default: 5000]
-h, --help Show help [boolean]
-V, --version Show version number [boolean]