Indeed it does appear in the console. However, I believe I have found the culprit, namely one of my routers. To elaborate, I have two of them, one used exclusively for my landline because I have really poor download speed if I connect to it ( about 4 MB ). The second one I use to connect to the Internet and it’s actually a 4G router which gives me better speed ( between 15 to 18 MB ) but it’s obviously less reliable.
Still, it’s always worked without issues so far which is why I didn’t suspect it until now. Having switched to the other router, it’s taking a fair bit longer to load the pages but no ERR_CONNECTION_TIMED_OUT so far. I’m glad to have found the cause of the problem but I’m no closer to finding out how to fix it.