This changelog belongs to our main JavaScript monitoring file. This changelog is covering both changes in the JavaScript as well as server level.




  • March 24th
    Our version upgrade to v4 (including web-vitals v3.5) caused bfcache attempts to not create a new navigationId.
    And although those TTFBs were collected -and thus preventing overall data from becoming skewed-, it was collected with an incorrect navigationtype, meaning that successful bfcache attempts were unexpectedly and thus incorrectly attributed to other navigation types.
  • March 22nd
    Our notRestoredReasons tracker has been adjusted to latest API specs
  • March 20th
    LCP entry's size (width * height) was added, representing the full surface area/dimension in pixels
    INP LoAF script's window was added
  • March 12th
    Following Google's deprecation of FID, we removed FID collection


  • February 28th
    We added a mandatory field "version" to our RUM beacons in a continued attempt to keep bot traffic out of our data.
  • February 27th
    "platform architecture" and "platform bitness" dimensions were removed
  • February 22nd
    Following a previous announced per mail, we upgraded the snippet of all accounts to version 4
    While users are free to choose the exact web-vitals library, we at enforced the minimum of web-vitals version 3.5
  • February 20th
    New dimension "(LCP) resource hint" was added, breaking down the bundled image priority dimension that would previously contain both fetchpriority and resource hint info in one.
  • February 15th
    removed navigator.connection.effectiveType
    While it isn't supporting 5g and 97.99% of mobile visitors and 98.04% of desktop visitors being reported as 4g.
    As a result, it could lead to fingerprinting while not giving additional insightful information.
  • February 14th
    Google ads and ad slot blocker detection was added
  • February 13th
    LoAF invoker and script function names were added
  • February 12th
    Preparation for bfcache notRestoredReasonAPI in Chrome 122


  • January 31st
    Moved some JS work to dev-mode-only to improve performance
  • January 8th
    "device processors" & "battery level" were removed



  • December 22nd
    Added SPA support for sites that are not meeting soft-navigations heuristics
    Deprecated filesize tracking due to lack of usage and Timing-Allow-Origin support from third parties
  • December 20th
    Added FCP tracking
    Extended FCP breakdown and introduced PageLoad breakdown
  • December 15th
    Added SPA support, including TTFB tracking
  • December 13th:
    Sequence number added
    norobots monitoring exclusion merged with URL rules
    Provide a custom timeout/delay before reporting metrics to batch together multiple metrics in one beacon
    webVitals metric threshold indicators are now merged/overruled by custom configured metric thresholds to reduce the amount of code
  • December 11th:
    Included more LoAF information, such as the total amount of LoAF's and the sum of work duration and render duration (up to FCP and PageLoad).
    Long Animation Frame Origin Trial needs to be enabled.


  • November 21st:
    excluded an additional category of bots (such as Contentking) via the Cloudfront Firewall


  • September 1st:
    added prerender to navigationtype dimension to identify this new deliveryType


  • August 18th:
    reduced data due to firewall configuration issues. This only affacted newly registerd domains and domains where URL's or tracking configuration had been changed recently.