"do JavaScript" doesn't return anything(?)

According to the DT dictionary and based on my playing around with it, “do JavaScript” doesn’t, well, can’t return a value. Is this correct because this is different than in Safari?

It would be very helpful to be able to get a return value, even if it would always just be a string. I am pretty sure I can just pass the URL to Safari, get my value, and then continue on—even if the page is not available anymore, I could pass the local path to the webarchive—so this probably isn’t worth it if it is very hard to implement. But if it is relatively easy, it would make my workflow way nicer. Thanks.

This command doesn’t work at all (neither in v2.0 nor in v1.x), the next beta will fix this.