luckyrat/gist:7803415810fb4c09c975

## gistfile1.js
// JSM for working out which globalproperties can be imported in a specific Firefox version.
// https://developer.mozilla.org/en-US/docs/Components.utils.importGlobalProperties
// I'm not certain availability always equates to functionality but it probably does
// and in any case it's a way to narrow down the more involved test for functionality of each property

// Run from browser toolbox scratchpad like:
// Components.utils.import("resource://test-importGlobalProperties-addon/test.jsm");

Components.utils.import("resource://gre/modules/devtools/Console.jsm");

let props = ["does-not-exist", "atob", "Blob", "btoa", "crypto", "CSS", "File",
            "indexedDB", "rtcIdentityProvider", "TextDecoder", "TextEncoder",
            "URL", "URLSearchParams", "XMLHttpRequest" ];

for (let prop of props)
{
    try {
        Components.utils.importGlobalProperties([].concat(prop));
        console.log(prop + " available");
    } catch (e)
    {
        console.log(e);
    }
}

var EXPORTED_SYMBOLS = [];
	// JSM for working out which globalproperties can be imported in a specific Firefox version.
	// https://developer.mozilla.org/en-US/docs/Components.utils.importGlobalProperties
	// I'm not certain availability always equates to functionality but it probably does
	// and in any case it's a way to narrow down the more involved test for functionality of each property

	// Run from browser toolbox scratchpad like:
	// Components.utils.import("resource://test-importGlobalProperties-addon/test.jsm");

	Components.utils.import("resource://gre/modules/devtools/Console.jsm");

	let props = ["does-not-exist", "atob", "Blob", "btoa", "crypto", "CSS", "File",
	"indexedDB", "rtcIdentityProvider", "TextDecoder", "TextEncoder",
	"URL", "URLSearchParams", "XMLHttpRequest" ];

	for (let prop of props)
	{
	try {
	Components.utils.importGlobalProperties([].concat(prop));
	console.log(prop + " available");
	} catch (e)
	{
	console.log(e);
	}
	}

	var EXPORTED_SYMBOLS = [];