Insurance statistics are clear that the leading cause of house fires is electrical failures. 93% of those (NFPA 2017 numbers) are based in the kitchen. The overwhelming majority of those are high current applications: range, oven, coffee maker. Overloading convenience outlets (splitters, poor condition, failed grounds, old installations that don't have GFCI protection) is common but a minority cause.
Slow cookers are very low draw appliances. They don't draw much more power than a table lamp. I would worry more about your hair dryer than a slow cooker.
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I'm a big fan of manual slow cookers. Simple is elegant and robust. My original Rival Crock-Pot is 50 years old. I replaced the cord about 20 years ago after it got caught in a cabinet door and damaged.
Instant Pot is a cult. Like most multi-function devices it doesn't do anything as well as built-for-purpose appliances. Further, you shouldn't need to keep the manual to a cooking appliance in a kitchen drawer to use a cooking appliance. Step back from the Kool-Aid.