A few days with no Internet is not enough to bring down civilization.
I hopefully stand corrected.
I didn't mean to suggest it would bring down civilization, just that it would cause more havoc than you might assume.
During the Texas blackouts was mobile internet available? Phone service? Was there food for the people who didn't receive deliveries?
Were you confident the government would restore service soon?
I grew up with frequent blackouts and I'm completely unfazed by anything on a 24-48-hour scale.
But -- and I hope I'm wrong! -- I see many societies growing more fragile and I would worry about what an infrastructure failure like that might mean to people who live much of their lives online.
A good receiver with a bit of antenna can easily give you access to radio stations thousands of kilometers away, as well as amateur radio operators.
And then you realize that these days mostly China and some american religious organizations invest heavily in shortwave broadcasts.
Location: Southern Sweden
That way, I don't need to worry as much about batteries, adapters, etc. and I can pretty easily find or make a 5V supply to power everything important
After superstorm Sandy here in New York I was left without power, heat, internet, gasoline or hot water for 2 weeks. Books, a crank radio, several thick blankets, an LED lantern and many batteries proved critical to making it through.
Remember that if an Internet outage extends for long enough (days?) in most of Europe then parts of your society will start to fall apart and lots of people will be completely freaking out, especially in the cities. (If it's a part of Europe that had wars fairly recently, people will probably not freak out as much.)
Thus your goal is to stay physically and mentally healthy. As a thought exercise, imagine going a week with no Internet, no mobile phone, and a lot of chaos on the streets: stores and gas stations mostly closed, possibly looting, etc. How exactly would you get through that?
I guess that's the prepper version.
The "half-day internet outages and I want to keep working" version is just have lots of documentation downloaded, plenty of source code too, and don't forget to take breaks: restoring your ability to concentrate is itself a work task.