The plug for my laptop is slowly changing colour, is it still safe to use until I get a new one?

So, right now my charger plug, that connects into the extension cord is slowly changing colour and it looks like it has small bumps, I can’t really tell though.

Is it because i’m using an extension cord or is it something else?

I use an extension cord instead of the actual outlet because, the outlet is too far from where I’m situated with the laptop. I know I can move but there isn’t much room in my apartment to move furniture around.

I’ve never had this problem with my older laptop and that was also plugged into an extension cord, but it was one of the bigger multiple outlet ones, with the ability to turn it on or off.

I just want to know is it still safe to use until I get a new one, or do I need to change my extension cord?

Laptop is - Acer Spin5 Input - 100-240V-50-80hz 1.2A Output- 19V-2.37A

Extension - 16 gauge calibre Wire type: SPT-3 6’7”/6pi 7po(2m) Length 0-50ft/pi(0-15m) 51-100ft/pi(16-30m) Max.Amperage: 13-10 I got this extension cord at Canadian tire

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