Firefox plugin not working with local LT

I had --allow-origin-all, took that from here (my bad):

Great idea. I was thinking out adding another option such as --allow-origin-all but that’s simpler.
I saw that stackoverflow thread, and a bunch of other discussions about the bug.

However, with --allow-origin, LT won’t start up at all, and with --allow-origin '*' the results are identical to --allow-origin-all. I am using LT 5.3.