@Stuk updates on this? There's a massive difference in performance between 3.1.5 and 3.5.0.

Still having this issue with the proposed workaround. Any tips?

I'd recommend switching to a different library, at least until this is merged. zip.js and fflate (my own library) are solid alternatives.

Could you merge master into this branch so that the unit tests will run? Thanks!

Could you merge master into this branch so that the unit tests will run? Thanks!

Thanks, I merged.

Can this merge now?

is this being worked on anymore?

What do you waiting for? @Stuk

set-immediate-shim is unacceptably slow.
The existence of this lib is a joke, it only provides setTimeout with "setImmediate" name. The absolutely useless "library".

Or setimmediate (of this pull request) is too big for you?

Since delay uses only the callback param of setImmediate

...just use the follow code instead of importing a library:

const setImmediate = globalThis.setImmediate || /*#__PURE__*/ (function() {
    const {port1, port2} = new MessageChannel();
    const queue = [];
    port1.onmessage = function() {
        const callback = queue.shift();
        callback();
    };
    return function setImmediateLike(callback) { // Simplified implementation: only callback argument.
        port2.postMessage(null);
        queue.push(callback);
    };
})();

The implementation of setImmediate based on MessageChannel is supported everywhere:
https://developer.mozilla.org/en-US/docs/Web/API/MessageChannel#browser_compatibility
https://caniuse.com/mdn-api_messagechannel_messagechannel

ES5 version to pass linter:

var setImmediate = typeof setImmediate === "function" ? setImmediate : /*#__PURE__*/ (function() {
    var channel = new MessageChannel();
    var port1 = channel.port1;
    var port2 = channel.port2;
    var queue = [];
    port1.onmessage = function() {
        var callback = queue.shift();
        callback();
    };
    return function setImmediateLike(callback) { // Simplified implementation: only callback argument.
        port2.postMessage(null);
        queue.push(callback);
    };
})();

Just put it before 404 line (also remove the import and the dependency):

All tests are passed. Works properly. And fast (as expected).

# pass 186
...
chromium { passed: 3301, failed: 0, total: 3301, runtime: 8940, tests: [] }
firefox { passed: 3301, failed: 0, total: 3301, runtime: 8585, tests: [] }
webkit { passed: 3301, failed: 0, total: 3301, runtime: 8367, tests: [] }