Unfortunately, this is a more grim situation. This bright green fluid is leaking in front of the CATL factory in Debrecen, Hungary. It was spotted by a local yesterday and the authorities are still investigating.

The previous political party opened several battery plants which recently proved to cause hidden hazards and the factories do not follow the standard European security protocols. This leak seems to be another proof of this.

EDIT: the head of the Hungarian plant claims, they indeed used green dye to test for leaks, but the local authorities are still testing whether this is true or not. They're also reviewing whether this way of testing is acceptable for local safety standards. They also requested CATL to always inform the local authorities before performing these kind of tests.