Mald is a combination of words mad and bald. Being mald/malding is a situation when you're so unnaturally mad it, figuratively speaking, makes you lose hair to a point where you become bald. It's usually used on the internet, especially on Twitch and in gamer communities.
- For older people, I'd compare it to common folk saying: "Stress makes your hair grey"
Some studies showed a link between hair loss or being bald and anger issues so it's also used when a regular bald person is normally angry.
I hate this fucking RNG... it's making me mald!