PSA - Brrrrrrrr
As the damn temps get lower I've been switching on the little space heater I keep near my work bench. It would be in October that I would remind staff at the high school I worked at - not to plug space heaters of any kind into a power strip of any kind. Just the space heater alone might take the power strip to 70-80% of its current max. And then you or someone plugs in some more stuff ... It was December and I was at work on the school campus and I got a call that classroom D7 has the smell of hot plastic. So I headed across campus. D7 was a science classroom and class was in session, There was a large flat top table structure at the front for experiments, in the space behind was the teacher, a space heater plugged into a power strip along with her laptop and some sensors and other equipment.
Literally as I entered the classroom turned and looked at the front of the room - the supply wires from the wall started to glow a faint red and the plastic was just turning liquid. There were some tongs on the table which I grabbed and pulled the plug from the wall. Danger averted and I took a long break. Long break, yeah.
Plug heaters directly into the wall socket and if you need a longer cord - spring for a appliance rated ext cord. My motto was always don't burn down your house or your day gig.
Discussion
Who needs heaters in the garage :P We prefer to freeze to death rather than than risk electrical fire (says the guy who leaves the hot glue gun plugged in over night by mistake way too often)
Luckily my workstation is in the basement. So Im in the vacinity of our furnace so it warms up down there

Bet that teacher was surprised............
Yeah, I work at a college, so I know all about this.
Also, if your cords are twisted and look more like coiled springs, replace them. What is happening is that the cords are being wound up, and the wires inside the cord are twisting around each other. Sooner or later, it is going to break, and then you will have an electrical fire on your hands, or even worse, a dangerous piece of equipment that could shock and kill you. Better to be safe than sorry .... replace those cords immediately!
Don't forget the ones with broken ground plugs, either. Those are there for a reason: to keep you safe. If you have a cord with a broken ground plug, toss it and get a new one.