u/Go0ners14

Hey everyone,

My MacBook Pro (M4) suddenly stopped displaying on my Samsung Odyssey G9 49" OLED (5120x1440). It worked flawlessly for about a year, then out of nowhere, nothing. I didn't knowingly update anything (though macOS auto-updates, so who knows). Currently on the latest macOS.

Symptom: When I plug in the USB-C, both the Mac and the monitor clearly detect that something is happening (they both react). I get a partial, glitchy image for a second, like in the photo, and then nothing.

Here's the key part: I plugged my iPhone into the exact same cable and the exact same setup, and it displays perfectly on the G9. So the cable, the monitor's input, and the physical connection all seem fine. It really looks like it's the Mac's video output / macOS negotiation.

What I've already tried / ruled out:

New cable (Maxonar). Same issue, so not the cable.
All USB-C ports on the Mac. Same result on every one.
Full monitor power cycle (unplugged from the wall). No change.
iPhone on the same cable = works perfectly. Rules out cable + monitor + port.

Given that the iPhone works on the same cable, I'm fairly convinced this is a macOS-side issue, probably something a recent update changed in the DisplayPort negotiation for this resolution/refresh rate. But I'm stuck on how to fix it without nuking the machine.

I have a strong tendency to just wipe and reinstall my Windows machines at the first sign of trouble, but this Mac has my entire work environment on it (I'm a DevOps engineer) and it's a pain to set back up, so I'd really love to avoid that.

Any ideas on what to try next? Happy to answer any questions.

Thanks in advance!

Hey everyone,

I made a small Firefox extension called FlagScout and wanted to share it here.

A bit of backstory: I'm an AWS cloud archi, and I kept needing specific info whenever I was editing DNS records or working on load balancers, or whatever. A few existing extensions did part of the job, but every single time one piece of info I needed was missing. So I built my own to have it all in one place. From there I started adding more general-purpose features, like the map. If there's something you need that isn't in there yet, don't hesitate to ask — that's basically how the extension grew in the first place.

It puts the hosting country flag of the site you're on right in your toolbar. Click the icon and you get a panel with everything I usually open three tabs to find:

IP + geolocation of the actual server you're talking to, plus the ISP
Tags when relevant: VPN, Proxy, Tor, Datacenter, Mobile
A map (OpenStreetMap) of where the server sits
WHOIS via RDAP — registrar, creation/expiry dates, nameservers, registrant
DNS records
VirusTotal reputation score (optional, needs a free API key)
A search box to look up any domain without visiting it
Your own public IP

On privacy: no tracking, no ads, no analytics. Nothing is ever sent to me. The only data stored is local (a geolocation cache, your API keys if you add any). It only talks to third-party services (ipapi.is, VirusTotal, etc.) to fetch the info you asked for.

It's Manifest V3, native JS, no bundler, and localized in EN / FR.

Why Firefox only? The code is 100% Chromium-compatible, but I refuse to pay Google's $5 fee to publish on the Chrome Web Store. So there's no Chrome release — though you can build it yourself and load it unpacked if you're on Chromium (instructions on github).

👉 Firefox: https://addons.mozilla.org/firefox/addon/flagscout/

It's free and I'm not monetizing it in any way. Would love feedback, bug reports, or feature ideas. Thanks for reading!

MacBook Pro M4 suddenly stopped outputting to my Samsung G9 49" OLED

FlagScout: Everything you need to know about the website you're visiting.