Errors aren't instances of Error

[fregante]

Run this in background.js:

browser.permissions.request({origins:["<all_urls>"]})
	.catch(err => console.log(err instanceof Error, err))

Firefox:

Chrome:

Source:

webextension-polyfill/src/browser-polyfill.js

Lines 97 to 98 in 716c90b

	if (extensionAPIs.runtime.lastError) {
	promise.reject(extensionAPIs.runtime.lastError);

Suggested code:

        if (extensionAPIs.runtime.lastError) {
          promise.reject(new Error(extensionAPIs.runtime.lastError.message));

[Rob--W]

Why would you want an Error instance here? It would be rather meaningless (stack, type doesn't add value).

[fregante]

Specifically i found out about this because I was using alert(error), which printed a nice 'Error: blah blah' in Firefox but '[object Object]' in Chrome. Additionally I was under the impression that polyfills are meant to standardize a set of APIs, so if something works on Firefox it should work the same in Chrome too, unless impossible (like the stack part)