IE Compat Bridge

Legacy browser compatibility checklist

Use this checklist before assuming an old intranet or WebForms page needs full IE mode. Some pages only depend on older JavaScript and DOM behavior and can be tested in Chrome with scoped compatibility patches.

Try IE Compat Bridge Check product limits

Good candidates for a Chrome patch layer

Old JavaScript event patterns

  • attachEvent instead of addEventListener
  • window.event or event.srcElement
  • returnValue or cancelBubble assumptions

Old navigation and frame patterns

  • Frameset startup pages that load the real app later
  • Loading.htm?url=... redirect pages
  • Selected document.frames aliases

Old picker and WebForms behavior

  • showModalDialog picker flows
  • Legacy WebForms date controls
  • Buttons or form actions that work in IE but do nothing in Chrome

Scoped internal testing

  • The old page mostly opens in Chrome already
  • You can test on a configured internal hostname
  • You want macOS and Windows Chrome users to join validation

When to use real IE mode instead

Windows-only browser technologies

  • ActiveX controls
  • VBScript or COM integration
  • Java applets or Silverlight plugins

Real Trident/document-mode dependency

  • IE7 or IE8 document mode is mandatory
  • The page renders differently because of the IE engine itself
  • The vendor explicitly requires Internet Explorer or Edge IE mode

Practical test flow

  1. Open the old page in current desktop Chrome and note what breaks.
  2. Separate rendering problems from JavaScript interaction problems.
  3. Check whether the failing feature depends on ActiveX, VBScript, COM, applets, or Trident.
  4. If not, test a scoped JS/DOM compatibility patch on one hostname.
  5. Keep Edge IE mode or a Windows VM as the fallback for true IE-only dependencies.
Download the trial build