Invisibility is fine.

So many people are freaking out because invisibility is a useful specialization now. Let me walk you through how to not get clowned on.

Light players: run thermal vision, sonar grenade, glitch grenade, or tracking dart. Any of these options will reveal any lights in their radius. Use these in the general area of objectives or whenever you see an enemy light.

Medium players: run glitch trap or proximity mines. This will reveal any lights in the general area for as long as they exist. You can use this to make sure your immediate area is cleared as well as to prevent any invisible lights from sneaking up on you.

Heavy players: use proximity mines or lockbolt. Proximinds create an area denial and the lock bolt will forcefully drag any invisible lights Within it's radius into view.

Universal counters in a pinch (all classes):

Any form of explosive will cause enough chaos to hit or spook an invisible light player. This includes any type of explosive weapon grenade or RPG/ C4/ 9/ breech charge.

FLASH BANGS. They may not reveal an enemy light but they will absolutely stop them from seeing you and reveal that they are in a room somewhere.

Goo or shields. Even if they are in a room if they can't reach you they can't hurt you.

If for some reason you or someone in your team doesn't carry any of these items you should reevaluate your gameplay. These are simply the gadgets you can use in an average Loadout to protect yourself. At any point you're also completely free to mag dump your weapon in a circle around you and are almost guaranteed to reveal any enemy lights. The only reason a invisible light should be able to catch you is if you are not playing with your team or not paying attention.