Chosen Solution
@morebrokenafter, So, unfortunately there isn’t one product that covers all these cases, but a few of them. DeoxIT D5 is what I use to remove oxidation along with a coarse piece of paper. For corroded battery terminals, leakage, water, etc. I mostly use citric acid if I have it on hand, or vinegar which I always have on hand. Never had a problem yet, but it does require a little elbow grease. All other cases I use CRC electronic cleaner, and I swear by that stuff. I’ve used it for a long time on everything from vintage audio to more modern stuff. Usually on the pots and hard to get to contact plates, because the nozzle and extender gets to the craziest places. I never do anything to USB contacts as I have never had it cause an issue. Audio connectors though, there I use them ALL the time. I can’t tell you how many “issues” I’ve “fixed” with simple oxidation removal.
Hi Just to add to the amazing answer from @geirandersen If you want to remove oxidation from SMD components cleaning with isopropyl alcohol and reflowing the solder joints with a little solder and flux makes the world of difference Here’s a example of what to expect:-) Before isopropyl alcohol,Flux and solder
After isopropyl alcohol,Flux and solder
Hopefully this helps Any questions please ask Thanks:-)