What are the minimum system requirements for the online editor?

The online editor doesn’t open on my machine; I simply see a blank white screen. What are the minimum system requirements on a Mac?

I’m using a late 2013 iMac running Safari Version 15.6.1 (15613., 15613) on macOS Catalina version 10.15.7 (19H2026). I cannot update the machine to a newer OS.

Do I need to buy a newer machine? Would a 2017 iMac work? It can run macOS Ventura 13.

The code editor uses CodeMirror, which claims on its website that it “supports browsers up from Internet Explorer 11”, which should cover Safari 15. But who knows how true that actually is. There could be a bug in the library, or Exercism’s own JavaScript code might be incompatible with this Safari version etc. etc.

The only way to know for sure why it doesn’t work and whether it would work on some other newer-but-not-newest version would be to actually test it on that version and inspect the JavaScript errors.

I don’t know if any of the Exercism employees or core contributors has access to older macs to test it. I don’t… In a professional setting, I would test such problems on https://www.browserstack.com/ which gives you access to many different OS + browser versions, but you have to pay to use it for longer than 1 minute long sessions.

I don’t either.

@quackdog If you go to Try CodeMirror, does that work for you?

Thank you for reporting the issue and letting us know. I’ll have access to an older iMac with an older version of Safari tomorrow, and then I will investigate the problem.

Have you tried using the online editor with a different browser?

@dem4ron Yes, indeed. I tried Brave and the UI works just fine. Thanks for suggesting this; I was close to pulling the trigger on a 2017 iMac purchase.

@ErikSchierboom CodeMirror did work on the original Safari browser which is where the issue persists. Does that mean there’s a bug on the Exercism side?

[at]angelikatyborska Thanks for the helpful context and information.


I’ve investigated the issue a bit, and it appears the problem is related to your Safari version. One of the highlight.js language functions uses a lookbehind regex pattern, which is only supported in Safari versions 16.4 and later.

There are a couple of issues with older versions of Safari that aren’t relevant to this thread. However, it is generally recommended to keep Safari updated, as it tends to lag behind other browsers in supporting certain features.


Safari versions are tied to macOS versions, and upgrading macOS is not always possible on older hardware (sometimes simply because the new version is way too slow on old hardware). Other browsers also drop support for older macOS versions at some point, so you can’t have the newest Chrome nor Firefox on an old mac either :disappointed:

PS: I’m speaking from experience. My mom once lost access to Duolingo because of those problems. She had to buy a new laptop even though old one was technically fully working, but the web moved on :cry:

That’s annoying!