Now they are all really scammy. I haven’t found a good code in years. All those sites do is forward you to the site with a referral link, if you buy something, coupon code or not, they get paid for the referral (and possibly future purchases you make).

Best I can suggest is to attack their business model. Open those sites in a private tab, copy/paste the codes to your normal browser.

Been using Garage for non critical stuff for a while, no problems.