JavaScript widget

For external sites, use the Three Levers Flow Embed script with FlowIframeEmbed.

Overview

Install FlowIframeEmbed in Salesforce and expose FlowIframeEmbed on a Site.
Define window.tlFlowEmbed on your external page.
Load three-levers-flow-embed.js.
The script builds query string (flow, endUrl, inputVars) and resizes iframe from frameHeight messages.

Note - Site URL path: Use https://your-site.force.com/site-prefix/apex/three_levers__FlowIframeEmbed (namespaced managed-package page), not /FlowIframeEmbed. See Salesforce setup.

Configure `window.tlFlowEmbed`

Define config before loading the script:

<div id="tl-flow-embed"></div>

<script>
  window.tlFlowEmbed = {
    embedUrl: 'https://your-site.force.com/site-prefix/apex/three_levers__FlowIframeEmbed',
    flow: 'Check_In_Dispatch',
    endUrl: 'https://yoursite.com/thanks',
    inputVars: ['recordId', 'source'],
    params: { recordId: '001xxx', source: 'homepage' },
    height: '75px',
    heightPadding: 20,
    ease: true,
    easeSpeed: 0.2,
    lazy: true,
    allowedOrigin: 'https://your-site.force.com'
  };
</script>

Load the script

<script src="https://cdn.jsdelivr.net/gh/jason-best/lightning-flow-iframe@latest/embed/three-levers-flow-embed.js" type="text/javascript"></script>

Or download from the v1.0.0 release.

Source: github.com/jason-best/lightning-flow-iframe

Three Levers hosted copy:

<script src="https://threelevers.com/assets/embed/three-levers-flow-embed.v1.js" type="text/javascript"></script>

Options

Property	Description	Required	Default
`embedUrl`	Site URL to `three_levers__FlowIframeEmbed` (no query string; path `/apex/three_levers__FlowIframeEmbed`)	Yes	—
`flow`	Flow API Developer Name	Yes	—
`endUrl`	Redirect URL when flow finishes	No	—
`inputVars`	Names of query params to pass as flow String inputs	No	none
`params`	Object of values for flow inputs (keys must be in `inputVars`)	No	—
`container`	CSS selector or element id for mount point	No	`#tl-flow-embed`
`height`	Initial iframe height	No	`75px`
`heightPadding`	Extra pixels added to reported height	No	`20`
`ease`	Smooth height transitions	No	`false`
`easeSpeed`	Transition time in seconds	No	`0.2`
`lazy`	`loading=\"lazy\"` on iframe	No	`false`
`allowedOrigin`	Restrict postMessage to this origin	No	all origins

See also: Querystring variables · Finish URL

Legacy `ifc` widget

Older docs used ifc and lighningiFrame.js. That script forwarded full parent query strings and used endurl (lowercase).

Current FlowIframeEmbed requires:

flow (API name)
endUrl (camelCase)
explicit inputVars allowlist

Legacy	Current
`ifc.iframeurl`	`embedUrl`
`ifc.endurl`	`endUrl`
`ifc.extraqs`	`params` + `inputVars`
Auto parent query string	Explicit `params` only