This is a very technical problems and those who knows the answer wouldn't have asked the questions and those who asked the questions, even with help, may even have bigger problems. It's like a bird falling from the sky asking for help and still waiting for help but everyone knows that throwing the bird up to the sky woudn't help but kill her.

From my experience, i have done several things when this happens:
- If I can restore from a backup, then I'd do it.
- If I can not, i will try to uninstall my module (sometimes I have to write a python script to do this)
- I can also try to reinstall the base/web module when i fixed the error in the javascript.
- If it is frontend, I can try to use developer mode to override the error to get the the interface to remove the code.

Even with so many years developing Odoo, I'd do everything on a dev system, then to a test system before production. And all the dev database and test databases are throwable